必对题解

代码如下：

#include <iostream>
using namespace std;
int main() {
	double pingshi,xiaoce,qimo,zongchengji;
    cin>>pingshi>>xiaoce>>qimo;
    zongchengji=pingshi/100.0*20+xiaoce/100.0*30+qimo/100.0*50;
    cout<<zongchengji;
	return 0;
}