WAP that uses structure to add and subtract times

Write a program that uses structure to add and subtract times

#include<stdio.h>

typedef struct times {
	int h;
	int m;
	int s;
} time;

time addTime(time t1, time t2) {
	time a = {0,0,0};
	a.s = t1.s + t2.s;
	if(a.s>=60) {
		a.s-=60;
		a.m+=1;
	}

	a.m += t1.m + t2.m;
	if(a.m >= 60) {
		a.m -= 60;
		a.h += 1;
	}

	a.h += t1.h + t2.h;
	return a;
}

time subTime(time t1, time t2){
	time a = {0,0,0};
	a.s = t1.s - t2.s;
	if(a.s < 0) {
		a.s += 60;
		a.m -= 1;
	}

	a.m += t1.m - t2.m;
	if(a.m < 0) {
		a.m += 60;
		a.h -= 1;
	}

	a.h += t1.h - t2.h;
	return a;
}

int main() {
	time t1 = {8,20,40},t2 = {5,50,30},ad,df;
	ad = addTime(t1,t2);
	df = subTime(t1,t2);
	printf("Add:\n %d : %d : %d\n",ad.h,ad.m,ad.s);
	printf("Sub:\n %d : %d : %d\n",df.h,df.m,df.s);
	return 0;
}

Output

Add:
14 : 11 : 10
Sub:
2 : 30 : 10