#include <bits/stdc++.h>
using namespace std;
using ll = long long;

int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);

    int n;
    cin >> n;
    vector<ll> a(n);
    for (int i = 0; i < n; i++) cin >> a[i];
    int k;
    cin >> k;
    vector<ll> b(n);
    for (int i=0;i<n;i++) {
        b[i]=a[i];
    }
    sort (b.begin(),b.end());
    unordered_map<ll, int> vitri;
    for (int i = 0; i < n; i++) {
        vitri[b[i]] = i;
    }
    for (int i = 0; i < n; i++) {
        if ((i % k) != (vitri[a[i]] % k)) {
            cout << "NO SOLUTION";
            return 0;
        }
    }

    ll ans = 0;
    vector<bool> vis(n, false);
    for (int s = 0; s < k; s++) {
        vector<int> id1;
        for (int i = s; i < n; i += k) {
            id1.push_back(i);
        }
        int sz = id1.size();
        unordered_map<int, int> id;
        for (int i = 0; i < sz; i++) {
            id[id1[i]] = i;
        }

        vector<int> p(sz);
        for (int i = 0; i < sz; i++) {
            p[i] = id[vitri[a[id1[i]]]];
        }

        vector<bool> used(sz, false);
        for (int i = 0; i < sz; i++) {
            if (used[i]) continue;
            int cur = i, len = 0;
            while (!used[cur]) {
                used[cur] = true;
                cur = p[cur];
                len++;
            }
            if (len > 1) ans += len - 1;
        }
    }

    cout << ans;
    return 0;
}