#include<bits/stdc++.h>
using namespace std;
char a[100],b[100];
int main(){
  int s;
  scanf("%s%s",&a,&b);
  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=(b[0]-'0')*10+b[1]-'0';
  int bm=(b[3]-'0')*10+b[4]-'0';
  int bs=(b[6]-'0')*10+b[7]-'0';
  int at=ah*3600+am*60+as;
  int bt=bh*3600+bm*60+bs;
  printf("%d",at-bt);
return 0;
}

/**************************************************************
	Problem: 1101
	User: wtq001
	Language: C++
	Result: Accepted
	Time:21 ms
	Memory:2076 kb
****************************************************************/