#include <stdio.h> int main() { int year = 0;//初始化 int month = 0; while (scanf("%d %d", &year, &month) != EOF) { //多组输入 if ((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0)) { //判断闰年 if (month == 2) { printf("29\n"); } else if (month == 4 || month == 6 || month == 9 || month == 11) { printf("30\n"); } else { printf("31\n"); } } else {//其他年份 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; }