View Code of Problem 56

#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <math.h>
 
int main()
{
	int a1,a2,a3,b1,b2,b3,c1,c2,c3,H;
	scanf("%d:%d:%d\n%d:%d:%d",&a1,&b1,&c1,&a2,&b2,&c2);
	a3=a2-a1;b3=b2-b1;c3=c2-c1;
	H=a3*3600+b3*60+c3;
 if(H<0) H=-H;
  a3=H/3600;
  b3=(H-3600*a3)/60;
  c3=H%60;
    printf("%d:%02d:%02d",abs(a3),abs(b3),abs(c3));
	return 0;
}