uva410.cpp

/*
 * Contest : UVA
 * Problem : 410 - Station Balance
 * Link    : https://vjudge.net/problem/UVA-410
 */

#include <bits/stdc++.h>
using namespace std;
using ll = long long;

#define fastio ios::sync_with_stdio(0); cin.tie(0);

int main() {
  fastio

  int c, s, set = 1, x;

  while (cin >> c >> s) {
    int n = 2 * c;
    int v[n] = {0};
    double avg = 0, imbalance = 0;

    for (int i = 0; i < s; i++) {
      cin >> v[i];
      avg += v[i];
    }
    avg /= c;

    sort(v, v + n);

    printf("Set #%i\n", set++);

    for (int i = 0; i < c; i++) {
      int chamber = v[i] + v[n - 1 - i];

      cout << " " << i << ":";
      if (v[i]) cout << " " << v[i];
      if (v[n - 1 - i]) cout << " " << v[n - 1 - i];
      cout << "\n";

      imbalance += abs(chamber - avg);
    }

    printf("IMBALANCE = %.5f\n\n", imbalance);
  }

  return 0;
}