int main(){
	int a,b,c,d,e,f,t=0,m=0,n=0;
	scanf("%d %d %d %d %d %d",&a,&b,&c,&d,&e,&f);
	while(a!=0){
		m=a*3600+b*60+c;
		n=(d+12)*3600+e*60+f;
		t=n-m;
		scanf("%d %d %d %d %d %d",&a,&b,&c,&d,&e,&f);
		printf("%d\n",t);
		
	}


	
	return 0;
}


