#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;

#define fi first
#define se second
#define pp push_back
#define all(x) (x).begin(), (x).end()
#define Ones(n) __builtin_popcount(n)
#define endl '\n'
#define mem(arrr, xx) memset(arrr,xx,sizeof arrr)
//#define int long long
#define debug(x) cout << (#x) << " = " << x << endl

void Gamal() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
#ifdef Clion
    freopen("input.txt", "r", stdin), freopen("output.txt", "w", stdout);
#endif
}

int dx[] = {+0, +0, -1, +1, +1, +1, -1, -1};
int dy[] = {-1, +1, +0, +0, +1, -1, +1, -1};

const double EPS = 1e-9;
const ll OO = 0X3F3F3F3F3F3F3F3F;
const int N = 2e5 + 5, INF = INT_MAX, MOD = 1e9 + 7, LOG = 20;

vector<int> adj[N], adjr[N], scc[N];
int vis[N], head[N], n, cnt;
stack<int> topo;

void dfs(int u) {
    vis[u] = 1;
    for (auto v: adj[u]) if (!vis[v]) dfs(v);
    topo.push(u);
}

void dfs2(int u, int g) {
    if (~head[u]) return;
    head[u] = g;
    for (auto v: adjr[u]) dfs2(v, g);
}

void dfs3(int u) {
    cnt++;
    for (auto v: scc[u])dfs3(v);
}


void kosaraju() {
    for (int i = 0; i < n; ++i) {
        vis[i] = false;
        head[i] = -1;
    }
    int comps = 0;
    for (int i = 0; i < n; i++)if (!vis[i]) dfs(i);

    while (!topo.empty()) {
        int u = topo.top();
        topo.pop();
        if (head[u] == -1) dfs2(u, comps++);
    }

    vector<int> in(n);
    for (int u = 0; u < n; ++u) {
        for (auto v: adj[u]) {
            if (head[u] == head[v])continue;
            scc[head[u]].push_back(head[v]);
            in[head[v]]++;
        }
    }
    ll ans = 1;
    for (int i = 0; i < comps; ++i) {
        if (in[i] == 0) {
            cnt = 1;
            dfs3(i);
            ans = ans * cnt % MOD;
        }
    }
    cout << (ans - 1 + MOD) % MOD;
}

void solve() {
    cin >> n;
    for (int i = 0; i < n; ++i) {
        int y;
        cin >> y;
        y--;
        adj[i].push_back(y);
        adjr[y].push_back(i);
    }
    kosaraju();
}


signed main() {
    Gamal();
    int t = 1;
//    cin >> t;
    while (t--) {
        solve();
    }
}