#include <stdio.h>
int main () {
//JSRUN引擎2.0,支持多达30种语言在线运行,全仿真在线交互输入输出。
int hour1,minute1;
int hour2,minute2;
scanf("%d %d", &hour1, &minute1);
scanf("%d %d", &hour2, &minute2);
int t1 = hour1 * 60 + minute1;
int t2 = hour2 * 60 + minute2;
int t = t1 - t2;
printf("时间差是%d小时%d分钟:", t/60, t%60);
return 0;
}