#include "bits/stdc++.h"
using namespace std;
#define int long long
#define REP(i, n) for (int i = 0; i < (int)n; ++i)
#define RREP(i, n) for (int i = (int)n - 1; i >= 0; --i)
#define FOR(i, s, n) for (int i = s; i < (int)n; ++i)
#define RFOR(i, s, n) for (int i = (int)n - 1; i >= s; --i)
#define ALL(a) a.begin(), a.end()
#define IN(a, x, b) (a <= x && x < b)
template<class T>inline void out(T t){cout << t << "\n";}
template<class T,class... Ts>inline void out(T t,Ts... ts){cout << t << " ";out(ts...);}
template<class T>inline bool CHMIN(T&a,T b){if(a > b){a = b;return true;}return false;}
template<class T>inline bool CHMAX(T&a,T b){if(a < b){a = b;return true;}return false;}
constexpr int INF = 1e18;
 
#define endl '\n'
#define IOS() ios_base::sync_with_stdio(0);cin.tie(0)

// 返り値: a と b の最大公約数


void solve(){
	int N;
	cin >> N;
	vector<int>a(N);
	REP(i,N){
		cin >> a[i];
	}
	vector<vector<int>>dp(N + 1,vector<int>(10010,INF));
	REP(i,10010)dp[0][i] = 0;
	REP(i,N){
		REP(j,10010){
			CHMIN(dp[i + 1][j],dp[i][j] + abs(a[i] - j));
		}
		REP(j,10009){
			CHMIN(dp[i + 1][j + 1],dp[i + 1][j]);
		}
	}
	out(*min_element(ALL(dp[N])));
}
 
signed main(){
	//IOS();
	int Q = 1;
	//cin >> Q;
	while(Q--)solve();
}