#include <bits/stdc++.h>
using namespace std;
int INF = 100000000;
int main(){
  int N;
  cin >> N;
  vector<int> Y(N);
  for (int i = 0; i < N; i++){
    cin >> Y[i];
  }
  vector<vector<int>> dp(N + 1, vector<int>(10001, INF));
  dp[0][0] = 0;
  for (int i = 0; i < N; i++){
    for (int j = 1; j <= 10000; j++){
      dp[i][j] = min(dp[i][j], dp[i][j - 1]);
    }
    for (int j = 0; j <= 10000; j++){
      dp[i + 1][j] = dp[i][j] + abs(j - Y[i]);
    }
  }
  int ans = INF;
  for (int i = 0; i <= 10000; i++){
    ans = min(ans, dp[N][i]);
  }
  cout << ans << endl;
}