11677

#include<stdio.h>
int main(){
int h1,h2,m,a,m1,m2;
scanf("%d%d%d%d",&h1,&m1,&h2,&m2);
while(h1!=0||h2!=0||m1!=0||m2!=0){
if (h1==0)
a=h2*60-m1+m2;
else if(h2==0)
a=(24-h1)*60-m1+m2;
else if(h1==h2)
a=24*60-m1+m2;
else if(h1<h2)
    a=(h2-h1)*60-m1+m2;
else
    a=(24-(h1-h2))*60-m1+m2;
    printf("%d\n",a);
scanf("%d%d%d%d",&h1,&m1,&h2,&m2);
}
return 0;}