C

#include <stdio.h>

/*Write a program to copy its input to its output, replacing each string of one or more blanks by a single blank*/

main()
{
    int c,d;
    while ((c=getchar())!=EOF)
    {   if (c=' ')
        {
			printf("value of d is %d",((d=getchar())!=EOF));
            if (d=' ')
            {
            	putchar(c);
            }
        }
        else
        	putchar(c);
    }
}