题解

#include<bits/stdc++.h>
using namespace std;
int main(){
	double a ,max = 0 ,min = 1000 ,sum = 0;
    for (int i = 1 ; i <= 4 ; i++){
        cin >> a;
        sum += a;
        if (a > max)  //max的判定
            max = a;
        if (a < min)  //min的判定
            min = a;
    }
    sum -= max + min;
    printf("%.2f" ,sum / 2);
    return 0;
}