#include<stdio.h>

int c, n;

int main()
{
   while( (c = getchar()) != EOF )
   {
      if( c == ' ' )
      {
         if( n )
            putchar(c);
      }
      else if( c == '\n' )
      {
         putchar(c);
         n = 0;
      }
      else
      {
         putchar(c);
         n = 1;
      }
   }
   return 0;
}