#include          #include         using     namespace     std  ;   int     countSubstr  (  string     &  s       int     k  )     {      int     n     =     s  .  length  ();      int     ans     =     0  ;          for     (  int     i  =  0  ;     i   <  n  ;     i  ++  )     {          // array to check if a character       // is present in substring i..j      vector   <  bool  >     map  (  26       0  );      int     distinctCnt     =     0  ;          for     (  int     j  =  i  ;     j   <  n  ;     j  ++  )     {          // if new character is present      // increment distinct count.      if     (  map  [  s  [  j  ]     -     'a'  ]     ==     false  )     {      map  [  s  [  j  ]     -     'a'  ]     =     true  ;      distinctCnt  ++  ;      }          // if distinct count is equal to k.      if     (  distinctCnt     ==     k  )     ans  ++  ;      }      }          return     ans  ;   }   int     main  ()     {      string     s     =     'abc'  ;      int     k     =     2  ;          cout      < <     countSubstr  (  s       k  );      return     0  ;   }   

   class   GfG     {      static     int     countSubstr  (  String     s       int     k  )     {      int     n     =     s  .  length  ();      int     ans     =     0  ;      for     (  int     i     =     0  ;     i      <     n  ;     i  ++  )     {      // array to check if a character       // is present in substring i..j      boolean  []     map     =     new     boolean  [  26  ]  ;      int     distinctCnt     =     0  ;      for     (  int     j     =     i  ;     j      <     n  ;     j  ++  )     {      // if new character is present      // increment distinct count.      if     (  !  map  [  s  .  charAt  (  j  )     -     'a'  ]  )     {      map  [  s  .  charAt  (  j  )     -     'a'  ]     =     true  ;      distinctCnt  ++  ;      }      // if distinct count is equal to k.      if     (  distinctCnt     ==     k  )     ans  ++  ;      }      }      return     ans  ;      }      public     static     void     main  (  String  []     args  )     {      String     s     =     'abc'  ;      int     k     =     2  ;      System  .  out  .  println  (  countSubstr  (  s       k  ));      }   }   

   def   countSubstr  (  s     k  ):   n   =   len  (  s  )   ans   =   0   for   i   in   range  (  n  ):   # array to check if a character    # is present in substring i..j   map   =   [  False  ]   *   26   distinctCnt   =   0   for   j   in   range  (  i     n  ):   # if new character is present   # increment distinct count.   if   not   map  [  ord  (  s  [  j  ])   -   ord  (  'a'  )]:   map  [  ord  (  s  [  j  ])   -   ord  (  'a'  )]   =   True   distinctCnt   +=   1   # if distinct count is equal to k.   if   distinctCnt   ==   k  :   ans   +=   1   return   ans   if   __name__   ==   '__main__'  :   s   =   'abc'   k   =   2   print  (  countSubstr  (  s     k  ))   

   using     System  ;   class     GfG     {      static     int     countSubstr  (  string     s       int     k  )     {      int     n     =     s  .  Length  ;      int     ans     =     0  ;      for     (  int     i     =     0  ;     i      <     n  ;     i  ++  )     {      // array to check if a character       // is present in substring i..j      bool  []     map     =     new     bool  [  26  ];      int     distinctCnt     =     0  ;      for     (  int     j     =     i  ;     j      <     n  ;     j  ++  )     {      // if new character is present      // increment distinct count.      if     (  !  map  [  s  [  j  ]     -     'a'  ])     {      map  [  s  [  j  ]     -     'a'  ]     =     true  ;      distinctCnt  ++  ;      }      // if distinct count is equal to k.      if     (  distinctCnt     ==     k  )     ans  ++  ;      }      }      return     ans  ;      }      static     void     Main  ()     {      string     s     =     'abc'  ;      int     k     =     2  ;      Console  .  WriteLine  (  countSubstr  (  s       k  ));      }   }   

   function     countSubstr  (  s       k  )     {      let     n     =     s  .  length  ;      let     ans     =     0  ;      for     (  let     i     =     0  ;     i      <     n  ;     i  ++  )     {      // array to check if a character       // is present in substring i..j      let     map     =     new     Array  (  26  ).  fill  (  false  );      let     distinctCnt     =     0  ;      for     (  let     j     =     i  ;     j      <     n  ;     j  ++  )     {      // if new character is present      // increment distinct count.      if     (  !  map  [  s  .  charCodeAt  (  j  )     -     'a'  .  charCodeAt  (  0  )])     {      map  [  s  .  charCodeAt  (  j  )     -     'a'  .  charCodeAt  (  0  )]     =     true  ;      distinctCnt  ++  ;      }      // if distinct count is equal to k.      if     (  distinctCnt     ===     k  )     ans  ++  ;      }      }      return     ans  ;   }   // Driver Code   let     s     =     'abc'  ;   let     k     =     2  ;   console  .  log  (  countSubstr  (  s       k  ));   

   #include          #include         using     namespace     std  ;   // function which finds the number of    // substrings with atmost k Distinct   // characters.   int     count  (  string     &  s       int     k  )     {      int     n     =     s  .  length  ();      int     ans     =     0  ;          // use sliding window technique      vector   <  int  >     freq  (  26       0  );      int     distinctCnt     =     0  ;      int     i     =     0  ;          for     (  int     j     =     0  ;     j      <     n  ;     j  ++  )     {          // expand window and add character      freq  [  s  [  j  ]     -     'a'  ]  ++  ;      if     (  freq  [  s  [  j  ]     -     'a'  ]     ==     1  )     distinctCnt  ++  ;          // shrink window if distinct characters exceed k      while     (  distinctCnt     >     k  )     {      freq  [  s  [  i  ]     -     'a'  ]  --  ;      if     (  freq  [  s  [  i  ]     -     'a'  ]     ==     0  )     distinctCnt  --  ;      i  ++  ;      }          // add number of valid substrings ending at j      ans     +=     j     -     i     +     1  ;      }          return     ans  ;   }   // function to find the number of substrings   // with exactly k Distinct characters.   int     countSubstr  (  string     &  s       int     k  )     {      int     n     =     s  .  length  ();      int     ans     =     0  ;          // subtract substrings with at most       // k-1 distinct characters from substrings      // with at most k distinct characters      ans     =     count  (  s       k  )     -     count  (  s       k  -1  );          return     ans  ;   }   int     main  ()     {      string     s     =     'abc'  ;      int     k     =     2  ;      cout      < <     countSubstr  (  s       k  );      return     0  ;   }   

   class   GfG     {      // function which finds the number of       // substrings with atmost k Distinct      // characters.      static     int     count  (  String     s       int     k  )     {      int     n     =     s  .  length  ();      int     ans     =     0  ;      // use sliding window technique      int  []     freq     =     new     int  [  26  ]  ;      int     distinctCnt     =     0  ;      int     i     =     0  ;      for     (  int     j     =     0  ;     j      <     n  ;     j  ++  )     {      // expand window and add character      freq  [  s  .  charAt  (  j  )     -     'a'  ]++  ;      if     (  freq  [  s  .  charAt  (  j  )     -     'a'  ]     ==     1  )     distinctCnt  ++  ;      // shrink window if distinct characters exceed k      while     (  distinctCnt     >     k  )     {      freq  [  s  .  charAt  (  i  )     -     'a'  ]--  ;      if     (  freq  [  s  .  charAt  (  i  )     -     'a'  ]     ==     0  )     distinctCnt  --  ;      i  ++  ;      }      // add number of valid substrings ending at j      ans     +=     j     -     i     +     1  ;      }      return     ans  ;      }      // function to find the number of substrings      // with exactly k Distinct characters.      static     int     countSubstr  (  String     s       int     k  )     {      int     n     =     s  .  length  ();      int     ans     =     0  ;      // Subtract substrings with at most       // k-1 distinct characters from substrings      // with at most k distinct characters      ans     =     count  (  s       k  )     -     count  (  s       k     -     1  );      return     ans  ;      }      public     static     void     main  (  String  []     args  )     {      String     s     =     'abc'  ;      int     k     =     2  ;      System  .  out  .  println  (  countSubstr  (  s       k  ));      }   }   

   # function which finds the number of    # substrings with atmost k Distinct   # characters.   def   count  (  s     k  ):   n   =   len  (  s  )   ans   =   0   # ese sliding window technique   freq   =   [  0  ]   *   26   distinctCnt   =   0   i   =   0   for   j   in   range  (  n  ):   # expand window and add character   freq  [  ord  (  s  [  j  ])   -   ord  (  'a'  )]   +=   1   if   freq  [  ord  (  s  [  j  ])   -   ord  (  'a'  )]   ==   1  :   distinctCnt   +=   1   # shrink window if distinct characters exceed k   while   distinctCnt   >   k  :   freq  [  ord  (  s  [  i  ])   -   ord  (  'a'  )]   -=   1   if   freq  [  ord  (  s  [  i  ])   -   ord  (  'a'  )]   ==   0  :   distinctCnt   -=   1   i   +=   1   # add number of valid substrings ending at j   ans   +=   j   -   i   +   1   return   ans   # function to find the number of substrings   # with exactly k Distinct characters.   def   countSubstr  (  s     k  ):   n   =   len  (  s  )   ans   =   0   # subtract substrings with at most    # k-1 distinct characters from substrings   # with at most k distinct characters   ans   =   count  (  s     k  )   -   count  (  s     k   -   1  )   return   ans   if   __name__   ==   '__main__'  :   s   =   'abc'   k   =   2   print  (  countSubstr  (  s     k  ))   

   using     System  ;   class     GfG     {      // function which finds the number of       // substrings with atmost k Distinct      // characters.      static     int     count  (  string     s       int     k  )     {      int     n     =     s  .  Length  ;      int     ans     =     0  ;      // use sliding window technique      int  []     freq     =     new     int  [  26  ];      int     distinctCnt     =     0  ;      int     i     =     0  ;      for     (  int     j     =     0  ;     j      <     n  ;     j  ++  )     {      // expand window and add character      freq  [  s  [  j  ]     -     'a'  ]  ++  ;      if     (  freq  [  s  [  j  ]     -     'a'  ]     ==     1  )     distinctCnt  ++  ;      // shrink window if distinct characters exceed k      while     (  distinctCnt     >     k  )     {      freq  [  s  [  i  ]     -     'a'  ]  --  ;      if     (  freq  [  s  [  i  ]     -     'a'  ]     ==     0  )     distinctCnt  --  ;      i  ++  ;      }      // add number of valid substrings ending at j      ans     +=     j     -     i     +     1  ;      }      return     ans  ;      }      // function to find the number of substrings      // with exactly k Distinct characters.      static     int     countSubstr  (  string     s       int     k  )     {      int     n     =     s  .  Length  ;      int     ans     =     0  ;      // subtract substrings with at most       // k-1 distinct characters from substrings      // with at most k distinct characters      ans     =     count  (  s       k  )     -     count  (  s       k     -     1  );      return     ans  ;      }      static     void     Main  ()     {      string     s     =     'abc'  ;      int     k     =     2  ;      Console  .  WriteLine  (  countSubstr  (  s       k  ));      }   }   

   // function which finds the number of    // substrings with atmost k Distinct   // characters.   function     count  (  s       k  )     {      let     n     =     s  .  length  ;      let     ans     =     0  ;      // use sliding window technique      let     freq     =     new     Array  (  26  ).  fill  (  0  );      let     distinctCnt     =     0  ;      let     i     =     0  ;      for     (  let     j     =     0  ;     j      <     n  ;     j  ++  )     {      // expand window and add character      freq  [  s  .  charCodeAt  (  j  )     -     'a'  .  charCodeAt  (  0  )]  ++  ;      if     (  freq  [  s  .  charCodeAt  (  j  )     -     'a'  .  charCodeAt  (  0  )]     ===     1  )      distinctCnt  ++  ;      // shrink window if distinct characters exceed k      while     (  distinctCnt     >     k  )     {      freq  [  s  .  charCodeAt  (  i  )     -     'a'  .  charCodeAt  (  0  )]  --  ;      if     (  freq  [  s  .  charCodeAt  (  i  )     -     'a'  .  charCodeAt  (  0  )]     ===     0  )      distinctCnt  --  ;      i  ++  ;      }      // add number of valid substrings ending at j      ans     +=     j     -     i     +     1  ;      }      return     ans  ;   }   // sunction to find the number of substrings   // with exactly k Distinct characters.   function     countSubstr  (  s       k  )     {      let     n     =     s  .  length  ;      let     ans     =     0  ;      // subtract substrings with at most       // k-1 distinct characters from substrings      // with at most k distinct characters      ans     =     count  (  s       k  )     -     count  (  s       k     -     1  );      return     ans  ;   }   // Driver Code   let     s     =     'abc'  ;   let     k     =     2  ;   console  .  log  (  countSubstr  (  s       k  ));