C++ valodā virkne ir objekts std::string klase, kas apzīmē rakstzīmju secību. Mēs varam veikt daudzas darbības ar virknēm, piemēram, savienošanu, salīdzināšanu, konvertēšanu utt.
C++ virknes piemērs
Apskatīsim vienkāršu C++ virknes piemēru.
#include using namespace std; int main( ) { string s1 = 'Hello'; char ch[] = { 'C', '+', '+'}; string s2 = string(ch); cout<<s1<<endl; cout<<s2<<endl; } < pre> <p>Output:</p> <pre> Hello C++ </pre> <hr> <h2>C++ String Compare Example</h2> <p>Let's see the simple example of string comparison using strcmp() function.</p> <pre> #include #include using namespace std; int main () { char key[] = 'mango'; char buffer[50]; do { cout<>buffer; } while (strcmp (key,buffer) != 0); cout<<'answer is correct!!'<<endl; return 0; } < pre> <p>Output:</p> <pre> What is my favourite fruit? apple What is my favourite fruit? banana What is my favourite fruit? mango Answer is correct!! </pre> <hr> <h2>C++ String Concat Example</h2> <p>Let's see the simple example of string concatenation using strcat() function.</p> <pre> #include #include using namespace std; int main() { char key[25], buffer[25]; cout << 'Enter the key string: '; cin.getline(key, 25); cout << 'Enter the buffer string: '; cin.getline(buffer, 25); strcat(key, buffer); cout << 'Key = ' << key << endl; cout << 'Buffer = ' << buffer<<endl; return 0; } < pre> <p>Output:</p> <pre> Enter the key string: Welcome to Enter the buffer string: C++ Programming. Key = Welcome to C++ Programming. Buffer = C++ Programming. </pre> <hr> <h2>C++ String Copy Example</h2> <p>Let's see the simple example of copy the string using strcpy() function.</p> <pre> #include #include using namespace std; int main() { char key[25], buffer[25]; cout << 'Enter the key string: '; cin.getline(key, 25); strcpy(buffer, key); cout << 'Key = '<< key << endl; cout << 'Buffer = '<< buffer<<endl; return 0; } < pre> <p>Output:</p> <pre> Enter the key string: C++ Tutorial Key = C++ Tutorial Buffer = C++ Tutorial </pre> <hr> <h2>C++ String Length Example</h2> <p>Let's see the simple example of finding the string length using strlen() function.</p> <pre> #include #include using namespace std; int main() { char ary[] = 'Welcome to C++ Programming'; cout << 'Length of String = ' << strlen(ary)<<endl; return 0; } < pre> <p>Output:</p> <pre> Length of String = 26 </pre> <h2>C++ String Functions</h2> <table class="table"> <tr> <th>Function</th> <th>Description</th> </tr> <tr> <td> int compare(const string& str) </td> <td>It is used to compare two string objects.</td> </tr> <tr> <td> <a href="/c-string-length">int length()</a> </td> <td>It is used to find the length of the string.</td> </tr> <tr> <td> void swap(string& str) </td> <td>It is used to swap the values of two string objects.</td> </tr> <tr> <td>string substr(int pos,int n)</td> <td>It creates a new string object of n characters.</td> </tr> <tr> <td> <a href="/c-string-size">int size()</a> </td> <td>It returns the length of the string in terms of bytes.</td> </tr> <tr> <td> void resize(int n) </td> <td>It is used to resize the length of the string up to n characters.</td> </tr> <tr> <td> <a href="/c-string-replace">string& replace(int pos,int len,string& str)</a> </td> <td>It replaces portion of the string that begins at character position pos and spans len characters.</td> </tr> <tr> <td> <a href="/c-string-append">string& append(const string& str)</a> </td> <td>It adds new characters at the end of another string object.</td> </tr> <tr> <td> char& at(int pos) </td> <td>It is used to access an individual character at specified position pos.</td> </tr> <tr> <td> <a href="/c-string-find">int find(string& str,int pos,int n)</a> </td> <td>It is used to find the string specified in the parameter.</td> </tr> <tr> <td> int find_first_of(string& str,int pos,int n) </td> <td>It is used to find the first occurrence of the specified sequence.</td> </tr> <tr> <td> int find_first_not_of(string& str,int pos,int n ) </td> <td>It is used to search the string for the first character that does not match with any of the characters specified in the string.</td> </tr> <tr> <td> int find_last_of(string& str,int pos,int n) </td> <td>It is used to search the string for the last character of specified sequence.</td> </tr> <tr> <td> int find_last_not_of(string& str,int pos) </td> <td>It searches for the last character that does not match with the specified sequence.</td> </tr> <tr> <td> string& insert() </td> <td>It inserts a new character before the character indicated by the position pos.</td> </tr> <tr> <td> int max_size() </td> <td>It finds the maximum length of the string.</td> </tr> <tr> <td> <a href="/c-string-push_back">void push_back(char ch)</a> </td> <td>It adds a new character ch at the end of the string.</td> </tr> <tr> <td> void pop_back() </td> <td>It removes a last character of the string.</td> </tr> <tr> <td> <a href="/c-string-assign">string& assign()</a> </td> <td>It assigns new value to the string.</td> </tr> <tr> <td> int copy(string& str) </td> <td>It copies the contents of string into another.</td> </tr> <tr> <td> char& back() </td> <td>It returns the reference of last character.</td> </tr> <tr> <td> Iterator begin() </td> <td>It returns the reference of first character.</td> </tr> <tr> <td> int capacity() </td> <td>It returns the allocated space for the string.</td> </tr> <tr> <td>const_iterator cbegin()</td> <td>It points to the first element of the string.</td> </tr> <tr> <td>const_iterator cend()</td> <td>It points to the last element of the string.</td> </tr> <tr> <td>void clear()</td> <td>It removes all the elements from the string.</td> </tr> <tr> <td>const_reverse_iterator crbegin()</td> <td>It points to the last character of the string.</td> </tr> <tr> <td>const_char* data()</td> <td>It copies the characters of string into an array.</td> </tr> <tr> <td>bool empty()</td> <td>It checks whether the string is empty or not.</td> </tr> <tr> <td>string& erase()</td> <td>It removes the characters as specified.</td> </tr> <tr> <td> char& front() </td> <td>It returns a reference of the first character.</td> </tr> <tr> <td> string&� operator+=() </td> <td>It appends a new character at the end of the string.</td> </tr> <tr> <td> string& operator=() </td> <td>It assigns a new value to the string.</td> </tr> <tr> <td>char operator[](pos)</td> <td>It retrieves a character at specified position pos.</td> </tr> <tr> <td> int rfind() </td> <td>It searches for the last occurrence of the string.</td> </tr> <tr> <td> iterator end() </td> <td>It references the last character of the string.</td> </tr> <tr> <td> reverse_iterator rend() </td> <td>It points to the first character of the string.</td> </tr> <tr> <td> void shrink_to_fit() </td> <td>It reduces the capacity and makes it equal to the size of the string.</td> </tr> <tr> <td> char* c_str() </td> <td>It returns pointer to an array that contains null terminated sequence of characters.</td> </tr> <tr> <td> const_reverse_iterator crend() </td> <td>It references the first character of the string.</td> </tr> <tr> <td> reverse_iterator rbegin() </td> <td>It reference the last character of the string.</td> </tr> <tr> <td>void reserve(inr len)</td> <td>It requests a change in capacity.</td> </tr> <tr> <td>allocator_type get_allocator();</td> <td>It returns the allocated object associated with the string.</td> </tr> </table></endl;></pre></endl;></pre></endl;></pre></'answer></pre></s1<<endl;> C++ virknes salīdzināšanas piemērs
Apskatīsim vienkāršu virkņu salīdzināšanas piemēru, izmantojot funkciju strcmp ().
#include #include using namespace std; int main () { char key[] = 'mango'; char buffer[50]; do { cout<>buffer; } while (strcmp (key,buffer) != 0); cout<<\'answer is correct!!\'<<endl; return 0; } < pre> <p>Output:</p> <pre> What is my favourite fruit? apple What is my favourite fruit? banana What is my favourite fruit? mango Answer is correct!! </pre> <hr> <h2>C++ String Concat Example</h2> <p>Let's see the simple example of string concatenation using strcat() function.</p> <pre> #include #include using namespace std; int main() { char key[25], buffer[25]; cout << 'Enter the key string: '; cin.getline(key, 25); cout << 'Enter the buffer string: '; cin.getline(buffer, 25); strcat(key, buffer); cout << 'Key = ' << key << endl; cout << 'Buffer = ' << buffer<<endl; return 0; } < pre> <p>Output:</p> <pre> Enter the key string: Welcome to Enter the buffer string: C++ Programming. Key = Welcome to C++ Programming. Buffer = C++ Programming. </pre> <hr> <h2>C++ String Copy Example</h2> <p>Let's see the simple example of copy the string using strcpy() function.</p> <pre> #include #include using namespace std; int main() { char key[25], buffer[25]; cout << 'Enter the key string: '; cin.getline(key, 25); strcpy(buffer, key); cout << 'Key = '<< key << endl; cout << 'Buffer = '<< buffer<<endl; return 0; } < pre> <p>Output:</p> <pre> Enter the key string: C++ Tutorial Key = C++ Tutorial Buffer = C++ Tutorial </pre> <hr> <h2>C++ String Length Example</h2> <p>Let's see the simple example of finding the string length using strlen() function.</p> <pre> #include #include using namespace std; int main() { char ary[] = 'Welcome to C++ Programming'; cout << 'Length of String = ' << strlen(ary)<<endl; return 0; } < pre> <p>Output:</p> <pre> Length of String = 26 </pre> <h2>C++ String Functions</h2> <table class="table"> <tr> <th>Function</th> <th>Description</th> </tr> <tr> <td> int compare(const string& str) </td> <td>It is used to compare two string objects.</td> </tr> <tr> <td> <a href="/c-string-length">int length()</a> </td> <td>It is used to find the length of the string.</td> </tr> <tr> <td> void swap(string& str) </td> <td>It is used to swap the values of two string objects.</td> </tr> <tr> <td>string substr(int pos,int n)</td> <td>It creates a new string object of n characters.</td> </tr> <tr> <td> <a href="/c-string-size">int size()</a> </td> <td>It returns the length of the string in terms of bytes.</td> </tr> <tr> <td> void resize(int n) </td> <td>It is used to resize the length of the string up to n characters.</td> </tr> <tr> <td> <a href="/c-string-replace">string& replace(int pos,int len,string& str)</a> </td> <td>It replaces portion of the string that begins at character position pos and spans len characters.</td> </tr> <tr> <td> <a href="/c-string-append">string& append(const string& str)</a> </td> <td>It adds new characters at the end of another string object.</td> </tr> <tr> <td> char& at(int pos) </td> <td>It is used to access an individual character at specified position pos.</td> </tr> <tr> <td> <a href="/c-string-find">int find(string& str,int pos,int n)</a> </td> <td>It is used to find the string specified in the parameter.</td> </tr> <tr> <td> int find_first_of(string& str,int pos,int n) </td> <td>It is used to find the first occurrence of the specified sequence.</td> </tr> <tr> <td> int find_first_not_of(string& str,int pos,int n ) </td> <td>It is used to search the string for the first character that does not match with any of the characters specified in the string.</td> </tr> <tr> <td> int find_last_of(string& str,int pos,int n) </td> <td>It is used to search the string for the last character of specified sequence.</td> </tr> <tr> <td> int find_last_not_of(string& str,int pos) </td> <td>It searches for the last character that does not match with the specified sequence.</td> </tr> <tr> <td> string& insert() </td> <td>It inserts a new character before the character indicated by the position pos.</td> </tr> <tr> <td> int max_size() </td> <td>It finds the maximum length of the string.</td> </tr> <tr> <td> <a href="/c-string-push_back">void push_back(char ch)</a> </td> <td>It adds a new character ch at the end of the string.</td> </tr> <tr> <td> void pop_back() </td> <td>It removes a last character of the string.</td> </tr> <tr> <td> <a href="/c-string-assign">string& assign()</a> </td> <td>It assigns new value to the string.</td> </tr> <tr> <td> int copy(string& str) </td> <td>It copies the contents of string into another.</td> </tr> <tr> <td> char& back() </td> <td>It returns the reference of last character.</td> </tr> <tr> <td> Iterator begin() </td> <td>It returns the reference of first character.</td> </tr> <tr> <td> int capacity() </td> <td>It returns the allocated space for the string.</td> </tr> <tr> <td>const_iterator cbegin()</td> <td>It points to the first element of the string.</td> </tr> <tr> <td>const_iterator cend()</td> <td>It points to the last element of the string.</td> </tr> <tr> <td>void clear()</td> <td>It removes all the elements from the string.</td> </tr> <tr> <td>const_reverse_iterator crbegin()</td> <td>It points to the last character of the string.</td> </tr> <tr> <td>const_char* data()</td> <td>It copies the characters of string into an array.</td> </tr> <tr> <td>bool empty()</td> <td>It checks whether the string is empty or not.</td> </tr> <tr> <td>string& erase()</td> <td>It removes the characters as specified.</td> </tr> <tr> <td> char& front() </td> <td>It returns a reference of the first character.</td> </tr> <tr> <td> string&� operator+=() </td> <td>It appends a new character at the end of the string.</td> </tr> <tr> <td> string& operator=() </td> <td>It assigns a new value to the string.</td> </tr> <tr> <td>char operator[](pos)</td> <td>It retrieves a character at specified position pos.</td> </tr> <tr> <td> int rfind() </td> <td>It searches for the last occurrence of the string.</td> </tr> <tr> <td> iterator end() </td> <td>It references the last character of the string.</td> </tr> <tr> <td> reverse_iterator rend() </td> <td>It points to the first character of the string.</td> </tr> <tr> <td> void shrink_to_fit() </td> <td>It reduces the capacity and makes it equal to the size of the string.</td> </tr> <tr> <td> char* c_str() </td> <td>It returns pointer to an array that contains null terminated sequence of characters.</td> </tr> <tr> <td> const_reverse_iterator crend() </td> <td>It references the first character of the string.</td> </tr> <tr> <td> reverse_iterator rbegin() </td> <td>It reference the last character of the string.</td> </tr> <tr> <td>void reserve(inr len)</td> <td>It requests a change in capacity.</td> </tr> <tr> <td>allocator_type get_allocator();</td> <td>It returns the allocated object associated with the string.</td> </tr> </table></endl;></pre></endl;></pre></endl;></pre></\'answer> C++ String Concat piemērs
Apskatīsim vienkāršu virkņu savienošanas piemēru, izmantojot funkciju strcat().
kartes java iterators
#include #include using namespace std; int main() { char key[25], buffer[25]; cout << 'Enter the key string: '; cin.getline(key, 25); cout << 'Enter the buffer string: '; cin.getline(buffer, 25); strcat(key, buffer); cout << 'Key = ' << key << endl; cout << 'Buffer = ' << buffer<<endl; return 0; } < pre> <p>Output:</p> <pre> Enter the key string: Welcome to Enter the buffer string: C++ Programming. Key = Welcome to C++ Programming. Buffer = C++ Programming. </pre> <hr> <h2>C++ String Copy Example</h2> <p>Let's see the simple example of copy the string using strcpy() function.</p> <pre> #include #include using namespace std; int main() { char key[25], buffer[25]; cout << 'Enter the key string: '; cin.getline(key, 25); strcpy(buffer, key); cout << 'Key = '<< key << endl; cout << 'Buffer = '<< buffer<<endl; return 0; } < pre> <p>Output:</p> <pre> Enter the key string: C++ Tutorial Key = C++ Tutorial Buffer = C++ Tutorial </pre> <hr> <h2>C++ String Length Example</h2> <p>Let's see the simple example of finding the string length using strlen() function.</p> <pre> #include #include using namespace std; int main() { char ary[] = 'Welcome to C++ Programming'; cout << 'Length of String = ' << strlen(ary)<<endl; return 0; } < pre> <p>Output:</p> <pre> Length of String = 26 </pre> <h2>C++ String Functions</h2> <table class="table"> <tr> <th>Function</th> <th>Description</th> </tr> <tr> <td> int compare(const string& str) </td> <td>It is used to compare two string objects.</td> </tr> <tr> <td> <a href="/c-string-length">int length()</a> </td> <td>It is used to find the length of the string.</td> </tr> <tr> <td> void swap(string& str) </td> <td>It is used to swap the values of two string objects.</td> </tr> <tr> <td>string substr(int pos,int n)</td> <td>It creates a new string object of n characters.</td> </tr> <tr> <td> <a href="/c-string-size">int size()</a> </td> <td>It returns the length of the string in terms of bytes.</td> </tr> <tr> <td> void resize(int n) </td> <td>It is used to resize the length of the string up to n characters.</td> </tr> <tr> <td> <a href="/c-string-replace">string& replace(int pos,int len,string& str)</a> </td> <td>It replaces portion of the string that begins at character position pos and spans len characters.</td> </tr> <tr> <td> <a href="/c-string-append">string& append(const string& str)</a> </td> <td>It adds new characters at the end of another string object.</td> </tr> <tr> <td> char& at(int pos) </td> <td>It is used to access an individual character at specified position pos.</td> </tr> <tr> <td> <a href="/c-string-find">int find(string& str,int pos,int n)</a> </td> <td>It is used to find the string specified in the parameter.</td> </tr> <tr> <td> int find_first_of(string& str,int pos,int n) </td> <td>It is used to find the first occurrence of the specified sequence.</td> </tr> <tr> <td> int find_first_not_of(string& str,int pos,int n ) </td> <td>It is used to search the string for the first character that does not match with any of the characters specified in the string.</td> </tr> <tr> <td> int find_last_of(string& str,int pos,int n) </td> <td>It is used to search the string for the last character of specified sequence.</td> </tr> <tr> <td> int find_last_not_of(string& str,int pos) </td> <td>It searches for the last character that does not match with the specified sequence.</td> </tr> <tr> <td> string& insert() </td> <td>It inserts a new character before the character indicated by the position pos.</td> </tr> <tr> <td> int max_size() </td> <td>It finds the maximum length of the string.</td> </tr> <tr> <td> <a href="/c-string-push_back">void push_back(char ch)</a> </td> <td>It adds a new character ch at the end of the string.</td> </tr> <tr> <td> void pop_back() </td> <td>It removes a last character of the string.</td> </tr> <tr> <td> <a href="/c-string-assign">string& assign()</a> </td> <td>It assigns new value to the string.</td> </tr> <tr> <td> int copy(string& str) </td> <td>It copies the contents of string into another.</td> </tr> <tr> <td> char& back() </td> <td>It returns the reference of last character.</td> </tr> <tr> <td> Iterator begin() </td> <td>It returns the reference of first character.</td> </tr> <tr> <td> int capacity() </td> <td>It returns the allocated space for the string.</td> </tr> <tr> <td>const_iterator cbegin()</td> <td>It points to the first element of the string.</td> </tr> <tr> <td>const_iterator cend()</td> <td>It points to the last element of the string.</td> </tr> <tr> <td>void clear()</td> <td>It removes all the elements from the string.</td> </tr> <tr> <td>const_reverse_iterator crbegin()</td> <td>It points to the last character of the string.</td> </tr> <tr> <td>const_char* data()</td> <td>It copies the characters of string into an array.</td> </tr> <tr> <td>bool empty()</td> <td>It checks whether the string is empty or not.</td> </tr> <tr> <td>string& erase()</td> <td>It removes the characters as specified.</td> </tr> <tr> <td> char& front() </td> <td>It returns a reference of the first character.</td> </tr> <tr> <td> string&� operator+=() </td> <td>It appends a new character at the end of the string.</td> </tr> <tr> <td> string& operator=() </td> <td>It assigns a new value to the string.</td> </tr> <tr> <td>char operator[](pos)</td> <td>It retrieves a character at specified position pos.</td> </tr> <tr> <td> int rfind() </td> <td>It searches for the last occurrence of the string.</td> </tr> <tr> <td> iterator end() </td> <td>It references the last character of the string.</td> </tr> <tr> <td> reverse_iterator rend() </td> <td>It points to the first character of the string.</td> </tr> <tr> <td> void shrink_to_fit() </td> <td>It reduces the capacity and makes it equal to the size of the string.</td> </tr> <tr> <td> char* c_str() </td> <td>It returns pointer to an array that contains null terminated sequence of characters.</td> </tr> <tr> <td> const_reverse_iterator crend() </td> <td>It references the first character of the string.</td> </tr> <tr> <td> reverse_iterator rbegin() </td> <td>It reference the last character of the string.</td> </tr> <tr> <td>void reserve(inr len)</td> <td>It requests a change in capacity.</td> </tr> <tr> <td>allocator_type get_allocator();</td> <td>It returns the allocated object associated with the string.</td> </tr> </table></endl;></pre></endl;></pre></endl;> C++ virknes kopijas piemērs
Apskatīsim vienkāršu piemēru virknes kopēšanai, izmantojot funkciju strcpy ().
#include #include using namespace std; int main() { char key[25], buffer[25]; cout << 'Enter the key string: '; cin.getline(key, 25); strcpy(buffer, key); cout << 'Key = '<< key << endl; cout << 'Buffer = '<< buffer<<endl; return 0; } < pre> <p>Output:</p> <pre> Enter the key string: C++ Tutorial Key = C++ Tutorial Buffer = C++ Tutorial </pre> <hr> <h2>C++ String Length Example</h2> <p>Let's see the simple example of finding the string length using strlen() function.</p> <pre> #include #include using namespace std; int main() { char ary[] = 'Welcome to C++ Programming'; cout << 'Length of String = ' << strlen(ary)<<endl; return 0; } < pre> <p>Output:</p> <pre> Length of String = 26 </pre> <h2>C++ String Functions</h2> <table class="table"> <tr> <th>Function</th> <th>Description</th> </tr> <tr> <td> int compare(const string& str) </td> <td>It is used to compare two string objects.</td> </tr> <tr> <td> <a href="/c-string-length">int length()</a> </td> <td>It is used to find the length of the string.</td> </tr> <tr> <td> void swap(string& str) </td> <td>It is used to swap the values of two string objects.</td> </tr> <tr> <td>string substr(int pos,int n)</td> <td>It creates a new string object of n characters.</td> </tr> <tr> <td> <a href="/c-string-size">int size()</a> </td> <td>It returns the length of the string in terms of bytes.</td> </tr> <tr> <td> void resize(int n) </td> <td>It is used to resize the length of the string up to n characters.</td> </tr> <tr> <td> <a href="/c-string-replace">string& replace(int pos,int len,string& str)</a> </td> <td>It replaces portion of the string that begins at character position pos and spans len characters.</td> </tr> <tr> <td> <a href="/c-string-append">string& append(const string& str)</a> </td> <td>It adds new characters at the end of another string object.</td> </tr> <tr> <td> char& at(int pos) </td> <td>It is used to access an individual character at specified position pos.</td> </tr> <tr> <td> <a href="/c-string-find">int find(string& str,int pos,int n)</a> </td> <td>It is used to find the string specified in the parameter.</td> </tr> <tr> <td> int find_first_of(string& str,int pos,int n) </td> <td>It is used to find the first occurrence of the specified sequence.</td> </tr> <tr> <td> int find_first_not_of(string& str,int pos,int n ) </td> <td>It is used to search the string for the first character that does not match with any of the characters specified in the string.</td> </tr> <tr> <td> int find_last_of(string& str,int pos,int n) </td> <td>It is used to search the string for the last character of specified sequence.</td> </tr> <tr> <td> int find_last_not_of(string& str,int pos) </td> <td>It searches for the last character that does not match with the specified sequence.</td> </tr> <tr> <td> string& insert() </td> <td>It inserts a new character before the character indicated by the position pos.</td> </tr> <tr> <td> int max_size() </td> <td>It finds the maximum length of the string.</td> </tr> <tr> <td> <a href="/c-string-push_back">void push_back(char ch)</a> </td> <td>It adds a new character ch at the end of the string.</td> </tr> <tr> <td> void pop_back() </td> <td>It removes a last character of the string.</td> </tr> <tr> <td> <a href="/c-string-assign">string& assign()</a> </td> <td>It assigns new value to the string.</td> </tr> <tr> <td> int copy(string& str) </td> <td>It copies the contents of string into another.</td> </tr> <tr> <td> char& back() </td> <td>It returns the reference of last character.</td> </tr> <tr> <td> Iterator begin() </td> <td>It returns the reference of first character.</td> </tr> <tr> <td> int capacity() </td> <td>It returns the allocated space for the string.</td> </tr> <tr> <td>const_iterator cbegin()</td> <td>It points to the first element of the string.</td> </tr> <tr> <td>const_iterator cend()</td> <td>It points to the last element of the string.</td> </tr> <tr> <td>void clear()</td> <td>It removes all the elements from the string.</td> </tr> <tr> <td>const_reverse_iterator crbegin()</td> <td>It points to the last character of the string.</td> </tr> <tr> <td>const_char* data()</td> <td>It copies the characters of string into an array.</td> </tr> <tr> <td>bool empty()</td> <td>It checks whether the string is empty or not.</td> </tr> <tr> <td>string& erase()</td> <td>It removes the characters as specified.</td> </tr> <tr> <td> char& front() </td> <td>It returns a reference of the first character.</td> </tr> <tr> <td> string&� operator+=() </td> <td>It appends a new character at the end of the string.</td> </tr> <tr> <td> string& operator=() </td> <td>It assigns a new value to the string.</td> </tr> <tr> <td>char operator[](pos)</td> <td>It retrieves a character at specified position pos.</td> </tr> <tr> <td> int rfind() </td> <td>It searches for the last occurrence of the string.</td> </tr> <tr> <td> iterator end() </td> <td>It references the last character of the string.</td> </tr> <tr> <td> reverse_iterator rend() </td> <td>It points to the first character of the string.</td> </tr> <tr> <td> void shrink_to_fit() </td> <td>It reduces the capacity and makes it equal to the size of the string.</td> </tr> <tr> <td> char* c_str() </td> <td>It returns pointer to an array that contains null terminated sequence of characters.</td> </tr> <tr> <td> const_reverse_iterator crend() </td> <td>It references the first character of the string.</td> </tr> <tr> <td> reverse_iterator rbegin() </td> <td>It reference the last character of the string.</td> </tr> <tr> <td>void reserve(inr len)</td> <td>It requests a change in capacity.</td> </tr> <tr> <td>allocator_type get_allocator();</td> <td>It returns the allocated object associated with the string.</td> </tr> </table></endl;></pre></endl;> C++ virknes garuma piemērs
Apskatīsim vienkāršu piemēru virknes garuma atrašanai, izmantojot funkciju strlen().
#include #include using namespace std; int main() { char ary[] = 'Welcome to C++ Programming'; cout << 'Length of String = ' << strlen(ary)<<endl; return 0; } < pre> <p>Output:</p> <pre> Length of String = 26 </pre> <h2>C++ String Functions</h2> <table class="table"> <tr> <th>Function</th> <th>Description</th> </tr> <tr> <td> int compare(const string& str) </td> <td>It is used to compare two string objects.</td> </tr> <tr> <td> <a href="/c-string-length">int length()</a> </td> <td>It is used to find the length of the string.</td> </tr> <tr> <td> void swap(string& str) </td> <td>It is used to swap the values of two string objects.</td> </tr> <tr> <td>string substr(int pos,int n)</td> <td>It creates a new string object of n characters.</td> </tr> <tr> <td> <a href="/c-string-size">int size()</a> </td> <td>It returns the length of the string in terms of bytes.</td> </tr> <tr> <td> void resize(int n) </td> <td>It is used to resize the length of the string up to n characters.</td> </tr> <tr> <td> <a href="/c-string-replace">string& replace(int pos,int len,string& str)</a> </td> <td>It replaces portion of the string that begins at character position pos and spans len characters.</td> </tr> <tr> <td> <a href="/c-string-append">string& append(const string& str)</a> </td> <td>It adds new characters at the end of another string object.</td> </tr> <tr> <td> char& at(int pos) </td> <td>It is used to access an individual character at specified position pos.</td> </tr> <tr> <td> <a href="/c-string-find">int find(string& str,int pos,int n)</a> </td> <td>It is used to find the string specified in the parameter.</td> </tr> <tr> <td> int find_first_of(string& str,int pos,int n) </td> <td>It is used to find the first occurrence of the specified sequence.</td> </tr> <tr> <td> int find_first_not_of(string& str,int pos,int n ) </td> <td>It is used to search the string for the first character that does not match with any of the characters specified in the string.</td> </tr> <tr> <td> int find_last_of(string& str,int pos,int n) </td> <td>It is used to search the string for the last character of specified sequence.</td> </tr> <tr> <td> int find_last_not_of(string& str,int pos) </td> <td>It searches for the last character that does not match with the specified sequence.</td> </tr> <tr> <td> string& insert() </td> <td>It inserts a new character before the character indicated by the position pos.</td> </tr> <tr> <td> int max_size() </td> <td>It finds the maximum length of the string.</td> </tr> <tr> <td> <a href="/c-string-push_back">void push_back(char ch)</a> </td> <td>It adds a new character ch at the end of the string.</td> </tr> <tr> <td> void pop_back() </td> <td>It removes a last character of the string.</td> </tr> <tr> <td> <a href="/c-string-assign">string& assign()</a> </td> <td>It assigns new value to the string.</td> </tr> <tr> <td> int copy(string& str) </td> <td>It copies the contents of string into another.</td> </tr> <tr> <td> char& back() </td> <td>It returns the reference of last character.</td> </tr> <tr> <td> Iterator begin() </td> <td>It returns the reference of first character.</td> </tr> <tr> <td> int capacity() </td> <td>It returns the allocated space for the string.</td> </tr> <tr> <td>const_iterator cbegin()</td> <td>It points to the first element of the string.</td> </tr> <tr> <td>const_iterator cend()</td> <td>It points to the last element of the string.</td> </tr> <tr> <td>void clear()</td> <td>It removes all the elements from the string.</td> </tr> <tr> <td>const_reverse_iterator crbegin()</td> <td>It points to the last character of the string.</td> </tr> <tr> <td>const_char* data()</td> <td>It copies the characters of string into an array.</td> </tr> <tr> <td>bool empty()</td> <td>It checks whether the string is empty or not.</td> </tr> <tr> <td>string& erase()</td> <td>It removes the characters as specified.</td> </tr> <tr> <td> char& front() </td> <td>It returns a reference of the first character.</td> </tr> <tr> <td> string&� operator+=() </td> <td>It appends a new character at the end of the string.</td> </tr> <tr> <td> string& operator=() </td> <td>It assigns a new value to the string.</td> </tr> <tr> <td>char operator[](pos)</td> <td>It retrieves a character at specified position pos.</td> </tr> <tr> <td> int rfind() </td> <td>It searches for the last occurrence of the string.</td> </tr> <tr> <td> iterator end() </td> <td>It references the last character of the string.</td> </tr> <tr> <td> reverse_iterator rend() </td> <td>It points to the first character of the string.</td> </tr> <tr> <td> void shrink_to_fit() </td> <td>It reduces the capacity and makes it equal to the size of the string.</td> </tr> <tr> <td> char* c_str() </td> <td>It returns pointer to an array that contains null terminated sequence of characters.</td> </tr> <tr> <td> const_reverse_iterator crend() </td> <td>It references the first character of the string.</td> </tr> <tr> <td> reverse_iterator rbegin() </td> <td>It reference the last character of the string.</td> </tr> <tr> <td>void reserve(inr len)</td> <td>It requests a change in capacity.</td> </tr> <tr> <td>allocator_type get_allocator();</td> <td>It returns the allocated object associated with the string.</td> </tr> </table></endl;> C++ virkņu funkcijas
| Funkcija | Apraksts |
|---|---|
| int salīdzināt (const string& str) | To izmanto, lai salīdzinātu divus virknes objektus. |
| int garums () | To izmanto, lai noteiktu virknes garumu. |
| nederīga mijmaiņa (string& str) | To izmanto, lai apmainītos ar divu virkņu objektu vērtībām. |
| virkne substr(int pos,int n) | Tas izveido jaunu virknes objektu ar n rakstzīmēm. |
| int size () | Tas atgriež virknes garumu baitos. |
| tukša izmēra maiņa (int n) | To izmanto, lai mainītu virknes garumu līdz n rakstzīmēm. |
| virkne&aizvietot(int poz,int len,string& str) | Tas aizstāj daļu no virknes, kas sākas ar rakstzīmes pozīciju un aptver len rakstzīmes. |
| virkne& pievienot(konst string& str) | Tas pievieno jaunas rakstzīmes cita virknes objekta beigās. |
| char& at(int pos) | To izmanto, lai piekļūtu atsevišķai rakstzīmei noteiktā pozīcijā. |
| int atrast(string& str,int poz,int n) | To izmanto, lai atrastu parametrā norādīto virkni. |
| int find_first_of(virkne& str,int poz,int n) | To izmanto, lai atrastu norādītās secības pirmo reizi. |
| int find_first_not_of(string& str,int poz,int n ) | To izmanto, lai virknē meklētu pirmo rakstzīmi, kas neatbilst nevienai no virknē norādītajām rakstzīmēm. |
| int find_last_of(virkne& str,int poz,int n) | To izmanto, lai virknē meklētu norādītās secības pēdējo rakstzīmi. |
| int find_last_not_of(string& str,int poz) | Tā meklē pēdējo rakstzīmi, kas neatbilst norādītajai secībai. |
| string& insert() | Tas ievieto jaunu rakstzīmi pirms rakstzīmes, ko norāda pozīcija poz. |
| int max_size() | Tas atrod maksimālo virknes garumu. |
| spēkā neesošs push_back(char ch) | Tas pievieno jaunu rakstzīmi ch virknes beigās. |
| tukšs pop_back() | Tas noņem virknes pēdējo rakstzīmi. |
| virkne&piešķirt() | Tas piešķir virknei jaunu vērtību. |
| int kopija (string& str) | Tas kopē virknes saturu citā. |
| char&back() | Tas atgriež atsauci uz pēdējo rakstzīmi. |
| Iteratora sākums () | Tas atgriež pirmās rakstzīmes atsauci. |
| iekšējā jauda () | Tas atgriež virknei piešķirto vietu. |
| const_iterator cbegin() | Tas norāda uz virknes pirmo elementu. |
| const_iterator cend() | Tas norāda uz pēdējo virknes elementu. |
| tukšums skaidrs () | Tas noņem visus elementus no virknes. |
| const_reverse_iterator crbegin() | Tas norāda uz virknes pēdējo rakstzīmi. |
| const_char* data() | Tas kopē virknes rakstzīmes masīvā. |
| bool tukšs () | Tas pārbauda, vai virkne ir tukša. |
| virkne&dzēst() | Tas noņem rakstzīmes, kā norādīts. |
| char&front() | Tas atgriež atsauci uz pirmo rakstzīmi. |
| string&� operators+=() | Tas pievieno jaunu rakstzīmi virknes beigās. |
| virkne& operators=() | Tas piešķir virknei jaunu vērtību. |
| char operators[](poz) | Tas izgūst rakstzīmi noteiktā pozīcijā. |
| int rfind() | Tā meklē pēdējo virknes gadījumu. |
| iterator end() | Tas atsaucas uz virknes pēdējo rakstzīmi. |
| reverse_iterator rend() | Tas norāda uz virknes pirmo rakstzīmi. |
| spēkā neesošs shrink_to_fit() | Tas samazina ietilpību un padara to vienādu ar virknes izmēru. |
| char* c_str() | Tas atgriež rādītāju uz masīvu, kurā ir nulles beigu rakstzīmju secība. |
| const_reverse_iterator crend() | Tas atsaucas uz virknes pirmo rakstzīmi. |
| reverse_iterator rbegin() | Tas atsaucas uz virknes pēdējo rakstzīmi. |
| tukšā rezerve (inr len) | Tas pieprasa mainīt kapacitāti. |
| allocator_type get_allocator(); | Tas atgriež piešķirto objektu, kas saistīts ar virkni. |