参考答案：

#include<iostream>
#include<algorithm>
using namespace std;
const int N = 100010;
int a[N];
int main()
{
    int n, t;
    cin >> n;
    t = n;
    int i = 0;
    double sum2 = 0;

    while (t--)
    {
        cin >> a[i];
        ++i;
    }
    sort(a, a + n);
    for (i = 0; i < n; ++i)
    {
        sum2 += a[i];
    }
    cout << a[n - 1] << ' ' << a[0] << ' ';
    printf("%.1lf", sum2 / (n * 1.0));

    return 0;
}