#include <bits/stdc++.h>
#define pb push_back
#define F first
#define S second
#define all(v) v.begin(),v.end()
#define Gondozu ios::sync_with_stdio(false);cout.tie(NULL);cin.tie(NULL);

using namespace std;
using ll = long long;
using pi = pair<int, int>;
using vi = vector<int>;
using vpi = vector <pair<int, int>>;
using vvi = vector <vector<int>>;

const int OO = 1e9 + 5;
const int N = 1e5 + 5;

const int MOD = 1e9+7;
ll add(ll a, ll b) {
    a += b;
    if (a >= MOD) a -= MOD;
    return a;
}
ll sub(ll a, ll b) {
    a -= b;
    if (a < 0) a += MOD;
    return a;
}
ll mul(ll a, ll b) { return a * b % MOD; }

vi adj[N], adjr[N];
bool vis[N], inCyc[N];
vi nodes, cyc;

void dfs(int v){
    vis[v] = true;
    nodes.push_back(v);

    for(int u : adj[v]){
        if(vis[u]){
            if(!inCyc[u]){
                for (int i = nodes.size()-1; i >= 0; --i) {
                    inCyc[nodes[i]] = true;
                    cyc.pb(nodes[i]);
                    if(nodes[i] == u)
                        break;
                }
            }
            continue;
        }
        dfs(u);
    }

    nodes.pop_back();
}

ll calc(int v, int par){
    ll ret = 1;
    for(int u : adjr[v]){
        if(u == par || inCyc[u])
            continue;
        ret = mul(ret, calc(u, v));
    }
    return add(ret, 1);
}

void TC()
{
    int n;
    cin >> n;
    int to;
    for (int i = 1; i <= n; ++i) {
        cin >> to;
        adj[i].push_back(to);
        adjr[to].push_back(i);
    }

    ll ans = 1;
    for (int i = 1; i <= n; ++i) {
        if(vis[i])
            continue;
        nodes.clear();
        cyc.clear();
        dfs(i);

        ll cur = 1;
        for(auto v : cyc){
            cur = mul(cur, sub(calc(v,v), 1));
        }
        ans = mul(ans, add(cur, 1));
    }

    cout << sub(ans,1);
}

int32_t main() {

    Gondozu
    int t = 1;
//    cin >> t;
    while (t--) {
        TC();
        cout << '\n';
    }
    return 0;
}