从键盘输入某年某月（包括闰年），用switch语句编程输出该年的改月拥有的天数。要求考虑闰年以及输入月份不在合法范围内的情况。已知闰年的2月有29天，平年有28天。
#include <stdio.h>
int main() {int year,month;scanf("%d %d",&year,&month);printf("Please enter year and month ");if((year%4==0 && year%100!=0 ) || year%400==0 ){ //判断是否是闰年switch (month) {case 2: 29;printf("There are 29 days in this month");break;case 1:case 3:case 5:case 7:case 8:case 10:case 12:printf("There are 31 days in this month");break;case 4:case 6:case 9:case 11:printf("There are 30 days in this month");break;}} else{switch (month) {case 2: 28;printf("There are 28 days in this month");break;case 1:case 3:case 5:case 7:case 8:case 10:case 12:printf("There are 31 days in this month");break;case 4:case 6:case 9:case 11:printf("There are 30 days in this month");break;}}return 0;
}