5-2 然后是几点 (15分)

#include <stdio.h>
int main()
{
int a,b;
scanf("%d %d", &a ,&b);
int h1,m1;
int a1;
h1=a/100;
m1=a%100;
int h2,m2;
if(b>=0)
{
h2=b/60;
m2=b%60;
int h3,m3;
m3=m1+m2;
h3=h1+h2;
if(m3>=60)
{
m3-=60;
h3+=1;
}
a1=h3*100+m3;
printf("%d",a1);
}
else
{
b*=-1;
h2=b/60;
m2=b%60;
int h3,m3;
m3=m1-m2;
h3=h1-h2;
if(m3<0)
{
m3+=60;
h3--;
}
a1=h3*100+m3;
printf("%d",a1);
}
}