USACO-T015: Ski Course Design

/*
ID: mickyta1
TASK: skidesign
LANG: C++
*/

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

const int N = 1000 + 5;

int arr[N];

int main(){
    freopen("skidesign.in", "r", stdin);
    freopen("skidesign.out", "w", stdout);

    int n;
    scanf("%d", &n);
    int lwb = 100;
    int upb = 0;
    for(int i = 1; i <= n; ++i){
        scanf("%d", &arr[i]);
        lwb = min(lwb, arr[i]);
        upb = max(upb, arr[i]);
    }
    if(upb - lwb <= 17){
        cout << "0\n";
        fclose(stdin);
        fclose(stdout);
        return 0;
    }
    int mn = 1e9;
    for(int l = lwb; l < upb - 17; ++l){
        int r = l + 17;
        int sum = 0;
        for(int j = 1; j <= n; ++j){
            if(arr[j] < l){
                int dif = l - arr[j];
                sum += dif * dif;
            } else if(arr[j] > r){
                int dif = arr[j] - r;
                sum += dif * dif;
            }
        }
        mn = min(mn, sum);
    }
    cout << mn << '\n';

    fclose(stdin);
    fclose(stdout);
    return 0;
}