#include<bits/stdc++.h>
using namespace std;
int main(){
    string s1,s2;
	int h1,h2,m1,m2,c1,c2; 
    cin>>s1>>s2;
    h1=(s1[0]-'0')*10+(s1[1]-'0');
    h2=(s2[0]-'0')*10+(s2[1]-'0');
    m1=(s1[3]-'0')*10+(s1[4]-'0');
    m2=(s2[3]-'0')*10+(s2[4]-'0');
    c1=(s1[6]-'0')*10+(s1[7]-'0');
    c2=(s2[6]-'0')*10+(s2[7]-'0');
    cout<<(h1*3600+m1*60+c1)-(h2*3600+m2*60+c2);
	return 0;
}

/**************************************************************
	Problem: 1101
	User: xuanhua
	Language: C++
	Result: Accepted
	Time:32 ms
	Memory:2076 kb
****************************************************************/