// C++ program to find the digit sum by    // repetitively Adding its digits   #include          using     namespace     std  ;   int     singleDigit  (  int     n  )     {      int     sum     =     0  ;      // Repetitively calculate sum until      // it becomes single digit      while     (  n     >     0     ||     sum     >     9  )     {      // If n becomes 0 reset it to sum       // and start a new iteration.      if     (  n     ==     0  )     {      n     =     sum  ;      sum     =     0  ;      }      sum     +=     n     %     10  ;      n     /=     10  ;      }      return     sum  ;   }   int     main  ()     {      int     n     =     1234  ;      cout      < <     singleDigit  (  n  );      return     0  ;   }   

   // C program to find the digit sum by    // repetitively Adding its digits   #include         int     singleDigit  (  int     n  )     {      int     sum     =     0  ;      // Repetitively calculate sum until      // it becomes single digit      while     (  n     >     0     ||     sum     >     9  )     {      // If n becomes 0 reset it to sum       // and start a new iteration.      if     (  n     ==     0  )     {      n     =     sum  ;      sum     =     0  ;      }      sum     +=     n     %     10  ;      n     /=     10  ;      }      return     sum  ;   }   int     main  ()     {      int     n     =     1234  ;      printf  (  '%d'       singleDigit  (  n  ));      return     0  ;   }   

   // Java program to find the digit sum by    // repetitively Adding its digits   class   GfG     {      static     int     singleDigit  (  int     n  )     {      int     sum     =     0  ;      // Repetitively calculate sum until      // it becomes single digit      while     (  n     >     0     ||     sum     >     9  )     {      // If n becomes 0 reset it to sum       // and start a new iteration.      if     (  n     ==     0  )     {      n     =     sum  ;      sum     =     0  ;      }      sum     +=     n     %     10  ;      n     /=     10  ;      }      return     sum  ;      }      public     static     void     main  (  String  []     args  )     {      int     n     =     1234  ;      System  .  out  .  println  (  singleDigit  (  n  ));      }   }   

   # Python program to find the digit sum by    # repetitively Adding its digits   def   singleDigit  (  n  ):   sum   =   0   # Repetitively calculate sum until   # it becomes single digit   while   n   >   0   or   sum   >   9  :   # If n becomes 0 reset it to sum    # and start a new iteration   if   n   ==   0  :   n   =   sum   sum   =   0   sum   +=   n   %   10   n   //=   10   return   sum   if   __name__   ==   '__main__'  :   n   =   1234   print  (  singleDigit  (  n  ))   

   // C# program to find the digit sum by    // repetitively Adding its digits   using     System  ;   class     GfG     {      static     int     singleDigit  (  int     n  )     {      int     sum     =     0  ;      // Repetitively calculate sum until      // it becomes single digit      while     (  n     >     0     ||     sum     >     9  )     {      // If n becomes 0 reset it to sum       // and start a new iteration.      if     (  n     ==     0  )     {      n     =     sum  ;      sum     =     0  ;      }      sum     +=     n     %     10  ;      n     /=     10  ;      }      return     sum  ;      }      static     void     Main  ()     {      int     n     =     1234  ;      Console  .  WriteLine  (  singleDigit  (  n  ));      }   }   

   // JavaScript program to find the digit sum by    // repetitively Adding its digits   function     singleDigit  (  n  )     {      let     sum     =     0  ;      // Repetitively calculate sum until      // it becomes single digit      while     (  n     >     0     ||     sum     >     9  )     {      // If n becomes 0 reset it to sum       // and start a new iteration.      if     (  n     ===     0  )     {      n     =     sum  ;      sum     =     0  ;      }      sum     +=     n     %     10  ;      n     =     Math  .  floor  (  n     /     10  );      }      return     sum  ;   }   // Driver Code   const     n     =     1234  ;   console  .  log  (  singleDigit  (  n  ));