#include<bits/stdc++.h>
using namespace std;
int main()
{
	char a[10],s[10];
	scanf("%s%s",&a,&s);
	int ah=(a[0]-'0')*10+(a[1]-'0');
	int am=(a[3]-'0')*10+(a[4]-'0');
	int as=(a[6]-'0')*10+(a[7]-'0');
	int bh=(s[0]-'0')*10+(s[1]-'0');
	int bm=(s[3]-'0')*10+(s[4]-'0');
	int bs=(s[6]-'0')*10+(s[7]-'0');
	int at=ah*3600+am*60+as,bt=bh*3600+bm*60+bs;
	cout<<at-bt;
}

/**************************************************************
	Problem: 1101
	User: zzz
	Language: C++
	Result: Accepted
	Time:82 ms
	Memory:2072 kb
****************************************************************/