Izmantojot ievades virkni un modeli, pārbaudiet, vai rakstzīmes ievades virknē atbilst tādai pašai secībai, ko nosaka shēmā esošās rakstzīmes. Pieņemsim, ka shēmā nebūs rakstzīmju dublikātu.
Piemēri:
char uz virkni java
Input: string = 'engineers rock' pattern = 'er'; Output: true All 'e' in the input string are before all 'r'. Input: string = 'engineers rock' pattern = 'egr'; Output: false There are two 'e' after 'g' in the input string. Input: string = 'engineers rock' pattern = 'gsr'; Output: false There are one 'r' before 's' in the input string.
Mēs esam apsprieduši divas pieejas šīs problēmas risināšanai.
Pārbaudiet, vai virkne atbilst rakstzīmju secībai, ko nosaka raksts, vai ne | 1. komplekts
Pārbaudiet, vai virkne atbilst rakstzīmju secībai, ko nosaka raksts, vai ne | 2. komplekts
Šajā pieejā mēs vispirms piešķiram etiķeti (vai secību) rakstzīmēm. Etiķetes tiek piešķirtas augošā secībā.
pavasara zābaki
Piemēram, modelis “gsr” ir apzīmēts šādi
'g' => 1 's' => 2 'r' => 3
Tas nozīmē “g” būs pirmais, tad “s”, tad “r”
Pēc iezīmju piešķiršanas rakstzīmēm mēs atkārtojam virknes rakstzīmes. Ceļojot mēs sekojam līdzi pēdējā apmeklētā varoņa etiķetei (vai secībai). Ja pašreizējā rakstzīme ir mazāka nekā iepriekšējā rakstzīme, mēs atgriežam false. Pretējā gadījumā mēs atjauninām pēdējo etiķeti. Ja visas rakstzīmes atbilst secībai, mēs atgriežam patiesu.
Zemāk ir tā ieviešana
C++// C++ program to find if a string follows order // defined by a given pattern. #include
// Java program to find if a string follows order // defined by a given pattern. class GFG { static int CHAR_SIZE = 256; // Returns true if characters of str follow // order defined by a given ptr. static boolean checkPattern(String str String pat) { int[] label = new int[CHAR_SIZE]; // Initialize all orders as -1 for (int i = 0; i < CHAR_SIZE; i++) label[i] = -1; // Assign an order to pattern characters // according to their appearance in pattern int order = 1; for (int i = 0; i < pat.length(); i++) { // give the pattern characters order label[pat.charAt(i)] = order; // increment the order order++; } // Now one by check if string characters // follow above order int last_order = -1; for (int i = 0; i < str.length(); i++) { if (label[str.charAt(i)] != -1) { // If order of this character is less // than order of previous return false. if (label[str.charAt(i)] < last_order) return false; // Update last_order for next iteration last_order = label[str.charAt(i)]; } } // return that str followed pat return true; } // Driver code public static void main(String[] args) { String str = 'engineers rock'; String pattern = 'gsr'; System.out.println(checkPattern(str pattern)); } } // This code is contributed by // sanjeev2552
# Python3 program to find if a string follows # order defined by a given pattern CHAR_SIZE = 256 # Returns true if characters of str follow # order defined by a given ptr. def checkPattern(Str pat): # Initialize all orders as -1 label = [-1] * CHAR_SIZE # Assign an order to pattern characters # according to their appearance in pattern order = 1 for i in range(len(pat)): # Give the pattern characters order label[ord(pat[i])] = order # Increment the order order += 1 # Now one by one check if string # characters follow above order last_order = -1 for i in range(len(Str)): if (label[ord(Str[i])] != -1): # If order of this character is less # than order of previous return false if (label[ord(Str[i])] < last_order): return False # Update last_order for next iteration last_order = label[ord(Str[i])] # return that str followed pat return True # Driver Code if __name__ == '__main__': Str = 'engineers rock' pattern = 'gsr' print(checkPattern(Str pattern)) # This code is contributed by himanshu77
// C# program to find if a string follows order // defined by a given pattern. using System; class GFG { static int CHAR_SIZE = 256; // Returns true if characters of str follow // order defined by a given ptr. static bool checkPattern(String str String pat) { int[] label = new int[CHAR_SIZE]; // Initialize all orders as -1 for (int i = 0; i < CHAR_SIZE; i++) label[i] = -1; // Assign an order to pattern characters // according to their appearance in pattern int order = 1; for (int i = 0; i < pat.Length; i++) { // give the pattern characters order label[pat[i]] = order; // increment the order order++; } // Now one by check if string characters // follow above order int last_order = -1; for (int i = 0; i < str.Length; i++) { if (label[str[i]] != -1) { // If order of this character is less // than order of previous return false. if (label[str[i]] < last_order) return false; // Update last_order for next iteration last_order = label[str[i]]; } } // return that str followed pat return true; } // Driver code public static void Main(String[] args) { String str = 'engineers rock'; String pattern = 'gsr'; Console.WriteLine(checkPattern(str pattern)); } } // This code is contributed by 29AjayKumar
<script> // Javascript program to find if a string follows order // defined by a given pattern. let CHAR_SIZE = 256; // Returns true if characters of str follow // order defined by a given ptr. function checkPattern(strpat) { let label = new Array(CHAR_SIZE); // Initialize all orders as -1 for (let i = 0; i < CHAR_SIZE; i++) label[i] = -1; // Assign an order to pattern characters // according to their appearance in pattern let order = 1; for (let i = 0; i < pat.length; i++) { // give the pattern characters order label[pat[i].charCodeAt(0)] = order; // increment the order order++; } // Now one by check if string characters // follow above order let last_order = -1; for (let i = 0; i < str.length; i++) { if (label[str[i].charCodeAt(0)] != -1) { // If order of this character is less // than order of previous return false. if (label[str[i].charCodeAt(0)] < last_order) return false; // Update last_order for next iteration last_order = label[str[i].charCodeAt(0)]; } } // return that str followed pat return true; } // Driver code let str = 'engineers rock'; let pattern = 'gsr'; document.write(checkPattern(str pattern)); // This code is contributed by rag2127 </script>
Izvade
false
Laika sarežģītība no šīs programmas ir O(n) ar nemainīgu papildu vietu (masīva etiķetes izmērs ir nemainīgs 256).
Palīgtelpa: O(256).
osi atsauces modelis tīklu veidošanā