#include <bits/stdc++.h>

using namespace std;

int main() {
    int a, b, c, d;
    scanf("%d:%d\n%d:%d", &a, &b, &c, &d);
    int ans = 0;
    while (b != d) {
        b ++;
        ans ++;
        if (b == 60) b = 0;
    }
    while (a != c) {
        a ++;
        ans ++;
        if (a == 24) a = 0;
    }
    cout << ans << endl;
    return 0;
}