#include <algorithm>
#include <iostream>
#include <cstring>
#include <vector>
#include <string>
#include <cmath>
using namespace std;
struct student{
	string name;
	double val;
};
double cnt[21];
vector <student> s;
bool cmp(student a, student b) {
	if (a.val == b.val) return a.name < b.name;
	return a.val > b.val;
}
int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	int n, m;
	cin >> n >> m;
	for (int i = 0; i < n; i++) {
		student s1;
		cin >> s1.name;
		double ki = 0.0;
		for (int j = 0; j < m; j++) {
			cin >> cnt[j];
			ki += cnt[j];
		}
		ki /= (double)m;
		for (int j = 0; j < m; j++) 
			s1.val += pow(cnt[j] - ki, 2);
		s1.val = sqrt(s1.val / (double)m);
		s.push_back(s1);
		memset(cnt, 0, sizeof(cnt));
	}
	sort(s.begin(), s.end(), cmp);
	for (int i = 0; i < min(n, 20); i++) 
		cout << s[i].name << '\n';
	return 0;
}

交了 n 次，这份60分， WA 了 #1 #4 #8 #10 。 求助 o(╥﹏╥)o