#include<bits/stdc++.h>
using namespace std;
int time(string s){
    int r=0;
    int h= (s[0]-'0')*10+(s[1]-'0');
    int m=(s[3]-'0')*10+(s[4]-'0');
    int e=(s[6]-'0')*10+(s[7]-'0');
    r=h*60*60+m*60+e;
    return r;
}
int main (){
    string s1,s2;
    cin>>s1>>s2;
    cout<<time(s1)-time(s2);
    return 0;
}
/**************************************************************
	Problem: 1101
	User: fuyijun
	Language: C++
	Result: Accepted
	Time:15 ms
	Memory:2076 kb
****************************************************************/