#include <bits/stdc++.h>
#ifdef LOCAL
#include <debug.hpp>
#else
#define debug(...) void(0)
#endif

template <typename T> struct SlopeTrick {
    // initialize as f(x) = 0
    SlopeTrick() : min_f(0), add_l(0), add_r(0) {}

    // argmin f(x), min f(x)
    std::tuple<T, T, T> query() const { return {top_L(), top_R(), min_f}; }

    // f(x) += b
    void add_const(const T& b) { min_f += b; }

    // f(x) += max(a - x, 0) \_
    void add_a_minus_x(const T& a) {
        min_f += std::max(T(0), a - top_R());
        push_R(a);
        push_L(pop_R());
    }

    // f(x) += max(x - a, 0) _/
    void add_x_minus_a(const T& a) {
        min_f += std::max(T(0), top_L() - a);
        push_L(a);
        push_R(pop_L());
    }

    // f(x) += |x - a| \/
    void add_abs(const T& a) {
        add_a_minus_x(a);
        add_x_minus_a(a);
    }

    // f(x) <- min_{y <= x} f(y) \/ -> \_
    void chmin_right() {
        while (!R.empty()) R.pop();
    }

    // f(x) <- min_{x <= y} f(y)
    void chmin_left() {
        while (!L.empty()) L.pop();
    }

    // f(x) <- min_{x - b <= y <= x - a} f(y)
    void shift(const T& a, const T& b) {
        assert(a <= b);
        add_l += a;
        add_r += b;
    }

    // f(x) <- f(x - a)
    void shift(const T& a) { shift(a, a); }

    // return f(x), f destructive
    T get_destructive(const T& x) {
        T res = min_f;
        while (!L.empty()) res += std::max(T(0), pop_L() - x);
        while (!R.empty()) res += std::max(T(0), x - pop_R());
        return res;
    }

    // f(x) += g(x), g destructive
    void merge_destructive(SlopeTrick& g) {
        if (g.size() < size()) {
            std::swap(min_f, g.min_f);
            std::swap(L, g.L);
            std::swap(R, g.R);
            std::swap(min_f, g.add_l);
            std::swap(min_f, g.add_r);
        }
        min_f += g.min_f;
        while (!g.L.empty()) add_a_minus_x(g.pop_L());
        while (!g.R.empty()) add_x_minus_a(g.pop_R());
    }

private:
    const T inf = std::numeric_limits<T>::max() / 2;
    T min_f;
    std::priority_queue<T, std::vector<T>, std::less<>> L;
    std::priority_queue<T, std::vector<T>, std::greater<>> R;
    T add_l, add_r;

    void push_L(const T& a) { L.emplace(a - add_l); }

    T top_L() const { return L.empty() ? -inf : L.top() + add_l; }

    T pop_L() {
        T res = top_L();
        if (!L.empty()) L.pop();
        return res;
    }

    void push_R(const T& a) { R.emplace(a - add_r); }

    T top_R() const { return R.empty() ? inf : R.top() + add_r; }

    T pop_R() {
        T res = top_R();
        if (!R.empty()) R.pop();
        return res;
    }

    size_t size() const { return L.size() + R.size(); }
};

using namespace std;

typedef long long ll;
#define all(x) begin(x), end(x)
constexpr int INF = (1 << 30) - 1;
constexpr long long IINF = (1LL << 60) - 1;
constexpr int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1};

template <class T> istream& operator>>(istream& is, vector<T>& v) {
    for (auto& x : v) is >> x;
    return is;
}

template <class T> ostream& operator<<(ostream& os, const vector<T>& v) {
    auto sep = "";
    for (const auto& x : v) os << exchange(sep, " ") << x;
    return os;
}

template <class T, class U = T> bool chmin(T& x, U&& y) { return y < x and (x = forward<U>(y), true); }

template <class T, class U = T> bool chmax(T& x, U&& y) { return x < y and (x = forward<U>(y), true); }

template <class T> void mkuni(vector<T>& v) {
    sort(begin(v), end(v));
    v.erase(unique(begin(v), end(v)), end(v));
}

template <class T> int lwb(const vector<T>& v, const T& x) { return lower_bound(begin(v), end(v), x) - begin(v); }

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int N;
    cin >> N;
    vector<int> A(N);
    cin >> A;

    sort(all(A));
    SlopeTrick<ll> ST;
    for (int i = 0; i < N; i++) {
        ST.chmin_right();
        ST.add_abs(A[i] - i);
    }

    ll ans = get<2>(ST.query());
    cout << ans << '\n';
    return 0;
}