#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const int N = 2e5+1;
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; }

vector<int> adj[N], adj_inv[N];
bool inCycle[N], vis[N];
int inDegree[N];

/**
 * calculates the number of ways to pick the subtree of v
 * @param v the subtree root
 * @return the number of ways to pick the subtree of v
 */
ll calc(int v){
    ll ways = 1;
    for(int u : adj_inv[v]){
        if(inCycle[u])
            continue;
        // pick or leave each child's subtree
        ways = mul(ways, add(calc(u), 1));
    }
    return ways;
}

int main() {
    int n;
    cin >> n;

    // each person has exactly one partner
    for (int i = 1; i <= n; ++i) {
        int partner;
        cin >> partner;
        adj[i].push_back(partner);
        adj_inv[partner].push_back(i);
        inDegree[partner]++;

        // assume all nodes inCycle, then exclude later.
        inCycle[i] = true;
    }

    // topological sort to get the inCycle nodes
    vector<int> free;
    for (int i = 1; i <= n; ++i) {
        if(inDegree[i] == 0)
            free.push_back(i);
    }

    while (!free.empty()){
        int node = free.back();
        free.pop_back();

        inCycle[node] = false;
        for(int u : adj[node]){
            inDegree[u]--;
            if(inDegree[u] == 0)
                free.push_back(u);
        }
    }

    vector<vector<int>> allCycles;
    // get a cycle
    vector<int> cycle;
    for (int i = 1; i <= n; ++i) {
        if(!inCycle[i] || vis[i])
            continue;
        cycle.clear();
        int v = i;
        do {
            cycle.push_back(v);
            vis[v] = true;
            v = adj[v][0];
        } while (v != i);
        allCycles.push_back(cycle);
    }

    // calculate number of ways to pick a subset of friends with their partners
    ll ans = 1;
    for(auto& cyc : allCycles){
        ll curWays = 1;
        for(int v : cyc)
            curWays = mul(curWays, calc(v));
        // pick or leave the cycle
        ans = mul(ans, add(curWays, 1));
    }
    // exclude the empty subset
    ans = sub(ans, 1);

    cout << ans;
    return 0;
}