111796

#include <iostream>
#include <bits/stdc++.h>

#define mp make_pair
#define pb push_back
#define eb emplace_back
#define sz(x) (int)x.size()
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)
#define FOR(i,a,b) for (int i = (a); i < (b); i++)
#define RFOR(i,b,a) for (int i = (b) - 1; i >= (a); i--)

using namespace std;

typedef unsigned long long ull;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef vector<int> veci;
typedef vector<bool> vecb;
typedef vector<vector<int>> vvi;
typedef vector<vector<bool>> vvb;

const int INF_I = 1e9;
const ll INF_LL = 1e18;

int n, m, l, timer = 0;
vector<list<int>> g;
veci tin, tout;
vvi up;

void dfs(int v, int p){
    tin[v] = timer++;
    up[v][0] = p;
    for (int i = 1; i <= l; i++)
        up[v][i] = up[up[v][i-1]][i-1];
    for (int i : g[v])
        dfs(i, v);
    tout[v] = timer++;
}

bool check(int v, int p){
    return (tin[p] <= tin[v] && tout[v] <= tout[p]);
}

int lca(int a, int b){
    if (check(a, b)) return b;
    if (check(b, a)) return a;
    for (int i = l; i>= 0; i--)
        if (!check(a, up[b][i]))
            b = up[b][i];
    return up[b][0];
}

int main() {

    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);

    cin >> n >> m;
    l = ceil(log((double)n) / log(2));

    g.assign(n, list<int>());
    tin.assign(n, 0);
    tout.assign(n, 0);
    up.assign(n, veci(l + 1));

    for (int i = 1; i < n; i++){
        int p;
        cin >> p;
        g[p].eb(i);
    }

    veci a(2*m + 1);
    ll x, y, z;
    cin >> a[1] >> a[2] >> x >> y >> z;
    for (int i = 3; i <= 2*m; i++)
        a[i] = (x * a[i-2] + y * a[i-1] + z) % (ll)n;
    dfs(0, 0);
    ll v = lca(a[1], a[2]);
    ll res = v;
    for (int i = 2; i <= m; i++)
        res += (v = lca(((ll)a[2*i-1] + v) % (ll)n, a[2*i]));

    cout << res << "\n";

    return 0;
}