timer

/*
 Author: 曹北健(37509)
 Result: AC Submission_id: 4202181
 Created at: Sun Mar 20 2022 21:04:09 GMT+0800 (China Standard Time)
 Problem: 5422  Time: 3 Memory: 1716
*/

#include <stdio.h>
int main()
{
    int h1, h2, h3, h4, m1, m2, m3, m4;
    int t1, t2, t3, t4;
    double r;
    scanf("%d:%d %d:%d\n", &h1, &m1, &h2, &m2);
    scanf("%d:%d %d:%d", &h3, &m3, &h4, &m4);
    t1 = h1*60 + m1;
    t2 = h2*60 + m2;
    t3 = h3*60 + m3;
    t4 = h4*60 + m4;
    if(t2 <= t3) {
        printf("G00D!\n");
    }
    else {
        if(t1 >= t4) {
            printf("0HN0!\n");
        }
        else {
            int a = 2*(t2 - t1) *(t4 - t3);
            if(t1 <= t3&&t2 <= t4) {
                r = - 1.0* (t2 - t3) *(t2 - t3) /a + 1.0;
                printf("%.8lf\n", r);
            }
            if(t3 < t1&&t2 <= t4) {
                r = 1.0*(2*t4 - t1 - t2) *(t2 - t1) /a;
                printf("%.8lf\n", r);
            }
            if(t1 <= t3&&t4 < t2) {
                r = 1.0*(t3 + t4 - 2*t1) *(t4 - t3) /a;
                printf("%.8lf\n", r);
            }
            if(t3 < t1&&t4 < t2) {
                r = 1.0*(t4 - t1) *(t4 - t1) /a;
                printf("%.8lf\n", r);
            }
        }
    }
    return 0;
}