#include <stdio.h>
int main(int argc, char *argv) {
int hour1,minute1;
int hour2,minute2;
scanf("%d %d",&hour1,&hour1);
scanf("%d %d",&hour2,&hour2);
int t1=hour160+minute1;
int t2=hour2*60+minute2;
int t=t2-t1;
printf("时间差是%d小时%d分钟",t/60,t%60);
return 0;
}
