蒟蒻求助```cpp
#include
using namespace std;
int main(){
int n,month,days;
bool is=false;
cin>>n>>month;
switch(n){
case 1:
if(n%400==0){
is=!is;
}
case 2:
if(n%4==0&&n%100!=0){
is=!is;
}
case 3:
if(n%400!=0&&n%4!=0&&n%100!=0){
is=false;
}
}
switch(month){
case 1:
case 3:
case 5:
case 7:
case 8:
case 10:
case 12:
days=31;break;
case 4:
case 6:
case 9:
case 11:
days=30;break;
case 2:
if(is){
days=29;
break;
}
else{
days=28;
break;
}
}
cout<<days;
return 0;
}
