题解 | #获得月份天数#

#include <stdio.h>
//a 是年份 ，b 是月份 ，利用数组访问对应下表就行了
void YearDay(int a, int b) {
    int arr[] = {0, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
    if (a % 4 == 0 && a % 100 != 0 || a % 400 == 0) {
        printf("%d\n", *(arr + b));
    } else {// *(arr + b) == arr[b] 这两个是等价的
        if (b == 2) {
            printf("%d\n", *(arr + b) - 1);
        } else {
            printf("%d\n", *(arr + b));
        }
    }
}
int main() {
    int a, b;
    while (scanf("%d %d", &a, &b) != EOF) {
        YearDay(a, b);
    }
    return 0;
}