Leidžiama ilgiausia bendra seka su permutacijomis

Duotos dvi eilutės mažosiomis raidėmis, raskite ilgiausią eilutę, kurios permutacijos yra duotų dviejų eilučių posekos. Ilgiausia išvesties eilutė turi būti surūšiuota.

Pavyzdžiai:  

Input : str1 = 'pink' str2 = 'kite' Output : 'ik' The string 'ik' is the longest sorted string whose one permutation 'ik' is subsequence of 'pink' and another permutation 'ki' is subsequence of 'kite'. Input : str1 = 'working' str2 = 'women' Output : 'now' Input : str1 = 'geeks'  str2 = 'cake' Output : 'ek' Input : str1 = 'aaaa'  str2 = 'baba' Output : 'aa' 
Rekomenduojama: išspręskite tai „ PRAKTIKA “, prieš pereinant prie sprendimo.

Idėja yra skaičiuoti simbolius abiejose eilutėse. 

  1. apskaičiuokite kiekvienos eilutės simbolių dažnį ir išsaugokite juos atitinkamuose skaičiaus masyvuose, tarkime, count1[], kai yra str1, ir count2[], jei tai yra str2.
  2. Dabar turime 26 simbolių masyvus. Taigi eikite count1[] ir prie bet kurio indekso 'i' pridėkite simbolį ('a'+i) gautoje eilutėje 'result' min(count1[i] count2[i]) kartus.
  3. Kadangi skaičiuojame masyvą didėjančia tvarka, galutiniai eilutės simboliai bus rūšiuojami.

Įgyvendinimas:

C++
   // C++ program to find LCS with permutations allowed   #include       using     namespace     std  ;   // Function to calculate longest string   // str1 --> first string   // str2 --> second string   // count1[] --> hash array to calculate frequency   // of characters in str1   // count[2] --> hash array to calculate frequency   // of characters in str2   // result --> resultant longest string whose   // permutations are sub-sequence of given two strings   void     longestString  (  string     str1       string     str2  )   {      int     count1  [  26  ]     =     {  0  }     count2  [  26  ]  =     {  0  };      // calculate frequency of characters      for     (  int     i  =  0  ;     i   <  str1  .  length  ();     i  ++  )      count1  [  str1  [  i  ]  -  'a'  ]  ++  ;      for     (  int     i  =  0  ;     i   <  str2  .  length  ();     i  ++  )      count2  [  str2  [  i  ]  -  'a'  ]  ++  ;      // Now traverse hash array      string     result  ;      for     (  int     i  =  0  ;     i   <  26  ;     i  ++  )      // append character ('a'+i) in resultant      // string 'result' by min(count1[i]count2i])      // times      for     (  int     j  =  1  ;     j   <=  min  (  count1  [  i  ]  count2  [  i  ]);     j  ++  )      result  .  push_back  (  'a'     +     i  );      cout      < <     result  ;   }   // Driver program to run the case   int     main  ()   {      string     str1     =     'geeks'       str2     =     'cake'  ;      longestString  (  str1       str2  );      return     0  ;   }   
Java
   //Java program to find LCS with permutations allowed   class   GFG     {   // Function to calculate longest String   // str1 --> first String   // str2 --> second String   // count1[] --> hash array to calculate frequency   // of characters in str1   // count[2] --> hash array to calculate frequency   // of characters in str2   // result --> resultant longest String whose   // permutations are sub-sequence of given two strings      static     void     longestString  (  String     str1       String     str2  )     {      int     count1  []     =     new     int  [  26  ]       count2  []     =     new     int  [  26  ]  ;      // calculate frequency of characters      for     (  int     i     =     0  ;     i      <     str1  .  length  ();     i  ++  )     {      count1  [  str1  .  charAt  (  i  )     -     'a'  ]++  ;      }      for     (  int     i     =     0  ;     i      <     str2  .  length  ();     i  ++  )     {      count2  [  str2  .  charAt  (  i  )     -     'a'  ]++  ;      }      // Now traverse hash array      String     result     =     ''  ;      for     (  int     i     =     0  ;     i      <     26  ;     i  ++  )     // append character ('a'+i) in resultant      // String 'result' by min(count1[i]count2i])      // times      {      for     (  int     j     =     1  ;     j      <=     Math  .  min  (  count1  [  i  ]       count2  [  i  ]  );     j  ++  )     {      result     +=     (  char  )(  'a'     +     i  );      }      }      System  .  out  .  println  (  result  );      }   // Driver program to run the case      public     static     void     main  (  String  []     args  )     {      String     str1     =     'geeks'       str2     =     'cake'  ;      longestString  (  str1       str2  );      }   }   /* This java code is contributed by 29AjayKumar*/   
Python3
   # Python 3 program to find LCS   # with permutations allowed   # Function to calculate longest string   # str1 --> first string   # str2 --> second string   # count1[] --> hash array to calculate frequency   # of characters in str1   # count[2] --> hash array to calculate frequency   # of characters in str2   # result --> resultant longest string whose   # permutations are sub-sequence   # of given two strings   def   longestString  (  str1     str2  ):   count1   =   [  0  ]   *   26   count2   =   [  0  ]   *   26   # calculate frequency of characters   for   i   in   range  (   len  (  str1  )):   count1  [  ord  (  str1  [  i  ])   -   ord  (  'a'  )]   +=   1   for   i   in   range  (  len  (  str2  )):   count2  [  ord  (  str2  [  i  ])   -   ord  (  'a'  )]   +=   1   # Now traverse hash array   result   =   ''   for   i   in   range  (  26  ):   # append character ('a'+i) in   # resultant string 'result' by   # min(count1[i]count2i]) times   for   j   in   range  (  1     min  (  count1  [  i  ]   count2  [  i  ])   +   1  ):   result   =   result   +   chr  (  ord  (  'a'  )   +   i  )   print  (  result  )   # Driver Code   if   __name__   ==   '__main__'  :   str1   =   'geeks'   str2   =   'cake'   longestString  (  str1     str2  )   # This code is contributed by ita_c   
C#
   // C# program to find LCS with   // permutations allowed   using     System  ;   class     GFG   {   // Function to calculate longest String   // str1 --> first String   // str2 --> second String   // count1[] --> hash array to calculate   // frequency of characters in str1   // count[2] --> hash array to calculate   // frequency of characters in str2   // result --> resultant longest String whose   // permutations are sub-sequence of   // given two strings   static     void     longestString  (  String     str1        String     str2  )   {      int     []  count1     =     new     int  [  26  ];      int     []  count2     =     new     int  [  26  ];      // calculate frequency of characters      for     (  int     i     =     0  ;     i      <     str1  .  Length  ;     i  ++  )      {      count1  [  str1  [  i  ]     -     'a'  ]  ++  ;      }      for     (  int     i     =     0  ;     i      <     str2  .  Length  ;     i  ++  )      {      count2  [  str2  [  i  ]     -     'a'  ]  ++  ;      }      // Now traverse hash array      String     result     =     ''  ;      for     (  int     i     =     0  ;     i      <     26  ;     i  ++  )          // append character ('a'+i) in resultant      // String 'result' by min(count1[i]count2i])      // times      {      for     (  int     j     =     1  ;      j      <=     Math  .  Min  (  count1  [  i  ]      count2  [  i  ]);     j  ++  )      {      result     +=     (  char  )(  'a'     +     i  );      }      }   Console  .  Write  (  result  );   }   // Driver Code   public     static     void     Main  ()   {      String     str1     =     'geeks'       str2     =     'cake'  ;      longestString  (  str1       str2  );   }   }   // This code is contributed   // by PrinciRaj1992   
PHP
      // PHP program to find LCS with   // permutations allowed   // Function to calculate longest string   // str1 --> first string   // str2 --> second string   // count1[] --> hash array to calculate frequency   // of characters in str1   // count[2] --> hash array to calculate frequency   // of characters in str2   // result --> resultant longest string whose   // permutations are sub-sequence of given two strings   function   longestString  (  $str1     $str2  )   {   $count1   =   array_fill  (  0     26     NULL  );   $count2   =   array_fill  (  0     26     NULL  );   // calculate frequency of characters   for   (  $i   =   0  ;   $i    <   strlen  (  $str1  );   $i  ++  )   $count1  [  ord  (  $str1  [  $i  ])   -   ord  (  'a'  )]  ++  ;   for   (  $i   =   0  ;   $i    <   strlen  (  $str2  );   $i  ++  )   $count2  [  ord  (  $str2  [  $i  ])   -   ord  (  'a'  )]  ++  ;   // Now traverse hash array   $result   =   ''  ;   for   (  $i   =   0  ;   $i    <   26  ;   $i  ++  )   // append character ('a'+i) in resultant   // string 'result' by min(count1[$i]   // count2[$i]) times   for   (  $j   =   1  ;   $j    <=   min  (  $count1  [  $i  ]   $count2  [  $i  ]);   $j  ++  )   $result   =   $result  .  chr  (  ord  (  'a'  )   +   $i  );   echo   $result  ;   }   // Driver Code   $str1   =   'geeks'  ;   $str2   =   'cake'  ;   longestString  (  $str1     $str2  );   // This code is contributed by ita_c   ?>   
JavaScript
    <  script  >   // Javascript program to find LCS with permutations allowed   function     min  (  a       b  )   {      if  (  a      <     b  )      return     a  ;      else      return     b  ;   }   // Function to calculate longest String   // str1 --> first String   // str2 --> second String   // count1[] --> hash array to calculate frequency   // of characters in str1   // count[2] --> hash array to calculate frequency   // of characters in str2   // result --> resultant longest String whose   // permutations are sub-sequence of given two strings   function     longestString  (     str1       str2  )      {      var     count1     =     new     Array  (  26  );      var     count2     =     new     Array  (  26  );      count1  .  fill  (  0  );      count2  .  fill  (  0  );      // calculate frequency of characters      for     (  var     i     =     0  ;     i      <     str1  .  length  ;     i  ++  )     {      count1  [  str1  .  charCodeAt  (  i  )     -  97  ]  ++  ;      }      for     (  var     i     =     0  ;     i      <     str2  .  length  ;     i  ++  )     {      count2  [  str2  .  charCodeAt  (  i  )     -     97  ]  ++  ;      }      // Now traverse hash array      var     result     =     ''  ;      for     (  var     i     =     0  ;     i      <     26  ;     i  ++  )             // append character ('a'+i) in resultant      // String 'result' by min(count1[i]count2i])      // times      {      for     (  var     j     =     1  ;     j      <=     min  (  count1  [  i  ]     count2  [  i  ]);     j  ++  )     {      result     +=     String  .  fromCharCode  (  97     +     i  );      }      }      document  .  write  (  result  );      }      var     str1     =     'geeks'  ;      var     str2     =     'cake'  ;      longestString  (  str1       str2  );   // This code is contributed by akshitsaxenaa09.    <  /script>   

Išvestis
ek 

Laiko sudėtingumas: O(m + n) kur m ir n yra įvesties eilučių ilgiai.
Pagalbinė erdvė: O(1)

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