用iostream就够了

#include<iostream>
using namespace std;
int main(){
	int a,b,c;
    char x;
    cin>>a>>x>>b>>x>>c;
    
    if(b==1 || b==3 || b==5 || b==7 || b==8 || b==10 || b==12){
     	if(c>=1&&c<=31){
        	cout<<"NO";   
        }
        else cout<<"YES";
        
    }
    else if(b==4 || b==6 || b==9 || b==11){
     	if(c>=1&&c<=30){
         	cout<<"NO";   
        }
        else cout<<"YES";
        
    }
    else if(b==2){
    	if(a%400==0){
            if(c>=1 && c<=29){
                cout<<"NO";
            }
            else cout<<"YES";
            
        }
        else if(a%100==0){
            if(c>=1 && c<=28){
				cout<<"NO"; 
            }
        	else cout<<"YES";
            
        }
        else if(a%4==0){
        	if(c>=1 && c<=29){
				cout<<"NO";
            }
            else cout<<"YES";
            
        }
        else{
			if(c>=1 && c<=28){
            	cout<<"NO";   
            }
            else cout<<"YES";
        }
    }
    else cout<<"YES";
    
    return 0;
}