这题很神奇，根本不需要判断5，只需要判断是否有且只有1个7就行了

#include<iostream>
using namespace std;
int main(){
    int a,b,c,cnt=0;
    cin>>a>>b>>c;
    if(a==7)    cnt++;
    if(b==7)    cnt++;
    if(c==7)    cnt++;
    if(cnt==1)  cout<<"YES"<<endl;
    else    cout<<"NO"<<endl;
    return 0;
}

简单，模拟即可。

#include <bits/stdc++.h>
using namespace std;

int a, b, c;
int main() {
     cin >> a >> b >> c;
     if(a == 5 and b == 5 and c == 7) cout << "YES";
     else if(a == 5 and b == 7 and c == 5) cout << "YES";
     else if(a == 7 and b == 5 and c == 5) cout << "YES";
     else cout << "NO";
     return 0;
}