typedef long long ll;
typedef long double ld;
#include <bits/stdc++.h>
using namespace std;
#define int long long

signed main(){
    ll n;
    std::cin >> n;
    vector<ll> a(n),b(n);
    for (int i = 0; i < n; i++) {
        std::cin >> a[i];
        a[i]--;
        b[a[i]]=i;
    }
    ll ans = 0;
    for (int i = 0; i < n; i++) {
        while(a[i]!=i){
            ll now = a[i];
            swap(a[i],a[b[a[i]-1]]);
            swap(b[now],b[now-1]);
            ans++;
        }
    }
    std::cout << ans << std::endl;
    
}