UVa 11958 Coming Home Solution

#include<stdio.h>
int main()
{
int i,j,t,n,ch,cm,ah[1000],am[1000],at[1000],d,ans;
while(scanf("%d",&t)==1)
{
for(j=1;j<=t;j++)
{
ans=2500;
scanf("%d",&n);
scanf("%d:%d",&ch,&cm);
for(i=0;i<n;i++)
{
scanf("%d:%d %d",&ah[i],&am[i],&at[i]);
d=ah[i]*60+am[i]-ch*60-cm+at[i];
if(d<at[i])
d=(ah[i]+24)*60+am[i]-ch*60-cm+at[i];
if(d<ans)
ans=d;
}
printf("Case %d: %d\n",j,ans);
}
}
}