题解 | #获得月份天数#

#include <stdio.h>
int main() {
    int year, month;
    while (scanf("%d %d", &year, &month) != EOF) {


        if ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0) {
            if (month == 2) {
                printf("29\n");
            } else if (month == 4 || month == 6 || month == 9 || month == 11) {
                printf("30\n");
            } else {
                printf("31\n");
            }
        } else {
            if (month == 2) {
                printf("28\n");
            } else if (month == 4 || month == 6 || month == 9 || month == 11) {
                printf("30\n");
            } else {
                printf("31\n");
            }
        }

    }
    return 0;
}