题解

#include<iostream>
using namespace std;
int main(){
    int a,b,c;
    cin>>a>>b>>c;
    if(a+b>c&&a+c>b&&b+c>a){
        if(a==b&&a==c&&b==c){
            cout<<"yes"<<endl;
        }else{
            cout<<"no"<<endl;
        }
        if(a==b||a==c||b==c){
            cout<<"yes"<<endl;
        }else{
            cout<<"no"<<endl;
        }
        cout<<"yes";
    }else{
        cout<<"no"<<endl;
        cout<<"no"<<endl;
        cout<<"no";
    }
    return 0;
}