#include<bits/stdc++.h>
using namespace std;
 
 
int num(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 s,s1;
   cin>>s>>s1;
   cout<<num(s)-num(s1)<<endl;
}