Dizenin bir kalıp tarafından tanımlanan karakterlerin sırasını takip edip etmediğini kontrol edin | 2'yi ayarla
Bir giriş dizesi ve bir kalıp verildiğinde, giriş dizesindeki karakterlerin, kalıpta bulunan karakterlerle belirlenen sırayı takip edip etmediği kontrol edilir. Desende yinelenen karakterler olmayacağını varsayalım.
Aynı soruna başka bir çözüm gönderildi Burada .
Örnekler:
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.
Buradaki fikir verilen diziyi verilen desene indirgemektir. Desende verilen karakterler için yalnızca karşılık gelen karakterleri dizede tutarız. Yeni dizede sürekli tekrarlanan karakterleri sileriz. Değiştirilen dize daha sonra verilen desene eşit olmalıdır. Son olarak, değiştirilmiş dizeyi verilen modelle karşılaştırırız ve buna göre doğruyu yanlışa döndürürüz.
İllüstrasyon:
str = 'bfbaeadeacc' pat[] = 'bac' 1) Remove extra characters from str (characters that are not present in pat[] str = 'bbaaacc' [f e and d are removed] 3) Removed consecutive repeating occurrences of characters str = 'bac' 4) Since str is same as pat[] we return true
Aşağıda yukarıdaki adımların uygulanması yer almaktadır.
// C++ code for the above approach #include #include using namespace std ; bool followsPattern ( string str string pattern ) { // Insert all characters of pattern in a hash set unordered_set < char > patternSet ; for ( int i = 0 ; i < pattern . length (); i ++ ) { patternSet . insert ( pattern [ i ]); } // Build modified string (string with characters only from pattern are taken) string modifiedStr = str ; for ( int i = str . length () - 1 ; i >= 0 ; i -- ) { if ( patternSet . find ( str [ i ]) == patternSet . end ()) { modifiedStr . erase ( i 1 ); } } // Remove more than one consecutive occurrences of pattern characters from modified string for ( int i = modifiedStr . length () - 1 ; i > 0 ; i -- ) { if ( modifiedStr [ i ] == modifiedStr [ i - 1 ]) { modifiedStr . erase ( i 1 ); } } // After above modifications the length of modified string must be same as pattern length if ( pattern . length () != modifiedStr . length ()) { return false ; } // And pattern characters must also be same as modified string characters for ( int i = 0 ; i < pattern . length (); i ++ ) { if ( pattern [ i ] != modifiedStr [ i ]) { return false ; } } return true ; } int main () { string str = 'engineers rock' ; string pattern = 'er' ; cout < < 'Expected: true Actual: ' < < followsPattern ( str pattern ) < < endl ; str = 'engineers rock' ; pattern = 'egr' ; cout < < 'Expected: false Actual: ' < < followsPattern ( str pattern ) < < endl ; str = 'engineers rock' ; pattern = 'gsr' ; cout < < 'Expected: false Actual: ' < < followsPattern ( str pattern ) < < endl ; str = 'engineers rock' ; pattern = 'eger' ; cout < < 'Expected: true Actual: ' < < followsPattern ( str pattern ) < < endl ; return 0 ; } // This code is contributed by adityashatmfh
Java // Java program to check if characters of a string follow // pattern defined by given pattern. import java.util.* ; public class OrderOfCharactersForPattern { public static boolean followsPattern ( String str String pattern ) { // Insert all characters of pattern in a hash set Set < Character > patternSet = neHashSet <> (); for ( int i = 0 ; i < pattern . length (); i ++ ) patternSet . add ( pattern . charAt ( i )); // Build modified string (string with characters only from // pattern are taken) StringBuilder modifiedString = new StringBuilder ( str ); for ( int i = str . length () - 1 ; i >= 0 ; i -- ) if ( ! patternSet . contains ( modifiedString . charAt ( i ))) modifiedString . deleteCharAt ( i ); // Remove more than one consecutive occurrences of pattern // characters from modified string. for ( int i = modifiedString . length () - 1 ; i > 0 ; i -- ) if ( modifiedString . charAt ( i ) == modifiedString . charAt ( i - 1 )) modifiedString . deleteCharAt ( i ); // After above modifications the length of modified string // must be same as pattern length if ( pattern . length () != modifiedString . length ()) return false ; // And pattern characters must also be same as modified string // characters for ( int i = 0 ; i < pattern . length (); i ++ ) if ( pattern . charAt ( i ) != modifiedString . charAt ( i )) return false ; return true ; } // Driver program int main () { String str = 'engineers rock' ; String pattern = 'er' ; System . out . println ( 'Expected: true Actual: ' + followsPattern ( str pattern )); str = 'engineers rock' ; pattern = 'egr' ; System . out . println ( 'Expected: false Actual: ' + followsPattern ( str pattern )); str = 'engineers rock' ; pattern = 'gsr' ; System . out . println ( 'Expected: false Actual: ' + followsPattern ( str pattern )); str = 'engineers rock' ; pattern = 'eger' ; System . out . println ( 'Expected: true Actual: ' + followsPattern ( str pattern )); return 0 ; } }
Python3 # Python3 program to check if characters of # a string follow pattern defined by given pattern. def followsPattern ( string pattern ): # Insert all characters of pattern in a hash set patternSet = set () for i in range ( len ( pattern )): patternSet . add ( pattern [ i ]) # Build modified string (string with characters # only from pattern are taken) modifiedString = string for i in range ( len ( string ) - 1 - 1 - 1 ): if not modifiedString [ i ] in patternSet : modifiedString = modifiedString [: i ] + modifiedString [ i + 1 :] # Remove more than one consecutive occurrences # of pattern characters from modified string. for i in range ( len ( modifiedString ) - 1 0 - 1 ): if modifiedString [ i ] == modifiedString [ i - 1 ]: modifiedString = modifiedString [: i ] + modifiedString [ i + 1 :] # After above modifications the length of # modified string must be same as pattern length if len ( pattern ) != len ( modifiedString ): return False # And pattern characters must also be same # as modified string characters for i in range ( len ( pattern )): if pattern [ i ] != modifiedString [ i ]: return False return True # Driver Code if __name__ == '__main__' : string = 'engineers rock' pattern = 'er' print ( 'Expected: true Actual:' followsPattern ( string pattern )) string = 'engineers rock' pattern = 'egr' print ( 'Expected: false Actual:' followsPattern ( string pattern )) string = 'engineers rock' pattern = 'gsr' print ( 'Expected: false Actual:' followsPattern ( string pattern )) string = 'engineers rock' pattern = 'eger' print ( 'Expected: true Actual:' followsPattern ( string pattern )) # This code is contributed by # sanjeev2552
C# // C# program to check if characters of a string follow // pattern defined by given pattern. using System ; using System.Collections.Generic ; using System.Text ; class GFG { public static bool followsPattern ( String str String pattern ) { // Insert all characters of pattern in a hash set HashSet < char > patternSet = new HashSet < char > (); for ( int i = 0 ; i < pattern . Length ; i ++ ) patternSet . Add ( pattern [ i ]); // Build modified string (string with characters // only from pattern are taken) StringBuilder modifiedString = new StringBuilder ( str ); for ( int i = str . Length - 1 ; i >= 0 ; i -- ) if ( ! patternSet . Contains ( modifiedString [ i ])) modifiedString . Remove ( i 1 ); // Remove more than one consecutive occurrences of pattern // characters from modified string. for ( int i = modifiedString . Length - 1 ; i > 0 ; i -- ) if ( modifiedString [ i ] == modifiedString [ i - 1 ]) modifiedString . Remove ( i 1 ); // After above modifications the length of modified string // must be same as pattern length if ( pattern . Length != modifiedString . Length ) return false ; // And pattern characters must also be same // as modified string characters for ( int i = 0 ; i < pattern . Length ; i ++ ) if ( pattern [ i ] != modifiedString [ i ]) return false ; return true ; } // Driver program public static void Main ( String [] args ) { String str = 'engineers rock' ; String pattern = 'er' ; Console . WriteLine ( 'Expected: true Actual: ' + followsPattern ( str pattern )); str = 'engineers rock' ; pattern = 'egr' ; Console . WriteLine ( 'Expected: false Actual: ' + followsPattern ( str pattern )); str = 'engineers rock' ; pattern = 'gsr' ; Console . WriteLine ( 'Expected: false Actual: ' + followsPattern ( str pattern )); str = 'engineers rock' ; pattern = 'eger' ; Console . WriteLine ( 'Expected: true Actual: ' + followsPattern ( str pattern )); } } // This code is contributed by 29AjayKumar
JavaScript < script > // Javascript program to check if characters of a string follow // pattern defined by given pattern. function followsPattern ( str pattern ) { // Insert all characters of pattern in a hash set let patternSet = new Set (); for ( let i = 0 ; i < pattern . length ; i ++ ) patternSet . add ( pattern [ i ]); // Build modified string (string with characters only from // pattern are taken) let modifiedString = ( str ). split ( '' ); for ( let i = str . length - 1 ; i >= 0 ; i -- ) if ( ! patternSet . has ( modifiedString [ i ])) modifiedString . splice ( i 1 ); // Remove more than one consecutive occurrences of pattern // characters from modified string. for ( let i = modifiedString . length - 1 ; i > 0 ; i -- ) if ( modifiedString [ i ] == modifiedString [ i - 1 ]) modifiedString . splice ( i 1 ); // After above modifications the length of modified string // must be same as pattern length if ( pattern . length != modifiedString . length ) return false ; // And pattern characters must also be same as modified string // characters for ( let i = 0 ; i < pattern . length ; i ++ ) if ( pattern [ i ] != modifiedString [ i ]) return false ; return true ; } // Driver program let str = 'engineers rock' ; let pattern = 'er' ; document . write ( 'Expected: true Actual: ' + followsPattern ( str pattern ) + '
' ); str = 'engineers rock' ; pattern = 'egr' ; document . write ( 'Expected: false Actual: ' + followsPattern ( str pattern ) + '
' ); str = 'engineers rock' ; pattern = 'gsr' ; document . write ( 'Expected: false Actual: ' + followsPattern ( str pattern ) + '
' ); str = 'engineers rock' ; pattern = 'eger' ; document . write ( 'Expected: true Actual: ' + followsPattern ( str pattern ) + '
' ); // This code is contributed by rag2127 < /script>
Çıkış:
Expected: true Actual: true Expected: false Actual: false Expected: false Actual: false Expected: true Actual: true
Zaman Karmaşıklığı: Yukarıdaki uygulamaların zaman karmaşıklığı aslında O(mn + n^2)'dir, çünkü karakterleri kaldırmak için deleteCharAt() kullanıyoruz. Yukarıdaki çözümü doğrusal zamanda çalışacak şekilde optimize edebiliriz. deleteCharAr() kullanmak yerine boş bir dize oluşturabilir ve ona yalnızca gerekli karakterleri ekleyebiliriz.
StringBuilder, giriş dizesinde işlem yapmak için kullanılır. Bunun nedeni, String'in değişmez bir nesne iken StringBuilder'ın değiştirilebilir olmasıdır. Yeni bir dize oluşturmak O(n) alanı alır, dolayısıyla ekstra alan O(n) olur.
Bu sorunu çözmek için iki yaklaşımı daha tartıştık.
Dizenin bir kalıp tarafından tanımlanan karakterlerin sırasını takip edip etmediğini kontrol edin | Set 1
Dizenin bir kalıp tarafından tanımlanan karakterlerin sırasını takip edip etmediğini kontrol edin | 3'lü ayarla
