建议降红

按照题意将三个值分别乘以 $0.2,0.3,0.5$ 即可。

#include<iostream>
using namespace std;
int main(){
    int a,b,c;
    cin >> a >> b >> c;
    int sum = a*0.2 + b*0.3 + c*0.5;
    cout << sum;
    return 0;
}