题解 | #获得月份天数#

#include <stdio.h>

int main() {
    int year, month;
    while (scanf("%d%d", &year, &month) != EOF) {
        if (month == 1 || month == 3 || month == 5 || month == 7 || month == 8 ||
                month == 10 || month == 12)
            printf("31");
        else if (month == 4 || month == 6 || month == 9 || month == 11)
            printf("30");
        else {
            if (year % 4 == 0 && year % 100 != 0 || year % 400 == 0)
                printf("29");
            else
                printf("28");
        }
        printf("\n");
    }
    return 0;
}

主要是注意闰年和平年中2月天数的不同