#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i = 0; i < (n);i++)
#define sz(x) int(x.size())
typedef long long ll;
typedef long double ld;
typedef pair<int,int> P;
constexpr int INF = 2e9;
constexpr int AMAX = 1001;
int main() {
  int n;
  cin >> n;
  vector<int> a(n);
  rep(i,n) cin >> a[i];
  vector<int> dp(AMAX, INF);
  dp[0] = 0;
  for (int i = 0; i < n; i++) {
    vector<int> cum(AMAX + 1, INF);
    for (int j = 0; j < AMAX; j++) {
      cum[j + 1] = min(cum[j], dp[j]);
    }
    for (int j = 0; j < AMAX; j++) {
      dp[j] = cum[j + 1];
      if (dp[j] != INF) dp[j] += abs(j - a[i]);
    }
  }

  int res = INF;
  for (int i = 0; i < AMAX; i++) res = min(res, dp[i]);
  cout << res << endl;
  return 0;
}