#include<bits/stdc++.h>

using namespace std;
using ll = long long;
const int INF = 1e9;
const int high = 1e4+1;

int main()
{
    int n; cin >> n;
    vector<int> a(n);
    for(int i = 0; i < n; i++)cin >> a[i];
    vector<vector<int>> dp(n + 1, vector<int>(high, INF)); //dp[i][j] := a[i]の段差j以下に行くときの最小コスト
    for(int i = 0; i < high; i++)dp[0][i] = 0;
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < high; j++) {
            dp[i + 1][j] = min(dp[i + 1][j], abs(a[i] - j) + dp[i][j]);
            if(j != 0)dp[i + 1][j] = min(dp[i + 1][j - 1], dp[i + 1][j]);
        }
    }
    cout << dp[n][high-1] << endl;
}