题解7

#include <iostream>
#include <vector>
#include <algorithm>
#include <iomanip>
using namespace std;

int main() {
int n;
cin >> n;
vector<double> heights(n);
for (int i = 0; i < n; ++i) {
cin >> heights[i];
}

// 找到最高和第二高的同学的位置
int max1_pos = 0, max2_pos = 0;
for (int i = 1; i < n; ++i) {
    if (heights[i] > heights[max1_pos]) {
        max2_pos = max1_pos;
        max1_pos = i;
    } else if (heights[i] > heights[max2_pos] || max1_pos == max2_pos) {
        max2_pos = i;
    }
}

// 交换最高和最左边
swap(heights[max1_pos], heights[0]);

// 交换第二高和最右边，但要确保第二高没有被交换到最左边
if (max2_pos == 0) {
    max2_pos = max1_pos;
}
swap(heights[max2_pos], heights[n - 1]);

// 输出结果
for (int i = 0; i < n; ++i) {
    cout << fixed << setprecision(2) << heights[i];
    if (i != n - 1) {
        cout << " ";
    }
}
cout << endl;

return 0;

}