#include <iostream>
#include <vector>
#include <string>
#include <iomanip>
#include <queue>
#include <cmath>
#include <algorithm>
#include <unordered_map>
#include <tuple>
#include <iomanip>
#include <stdio.h>
#include <map>
#include <bitset>
#include <set>
#include <stack>
#include <queue>
#include <unordered_set>
#include <cassert>
#include <stdlib.h>
#include <time.h>
#include <random>


//#pragma GCC optimize("Ofast,no-stack-protector")
//#pragma GCC target("sse,sse2,sse3,sse3,sse4")
//#pragma GCC optimize("unroll-loops")
//#pragma GCC optimize("fast-math")
//#pragma GCC target("avx2")
//#pragma GCC optimize("section-anchors")
//#pragma GCC optimize("profile-values,profile-reorder-functions,tracer")
//#pragma GCC optimize("vpt")
//#pragma GCC optimize("rename-registers")
//#pragma GCC optimize("move-loop-invariants")
//#pragma GCC optimize("unswitch-loops")
//#pragma GCC optimize("function-sections")
//#pragma GCC optimize("data-sections")

#define int long long
#define ll long long
#define ull unsigned long long
#define all(a) (a).begin(), (a).end()
#define pii pair<int, int>
#define pb push_back
#define ld long double


using namespace std;

//const int INF = 1e17;
//const int mod = 2600000069;
//const int p = 179;
const int MAXN = 1e5 + 10;
const int logn = 23;

int n, m;
int up[MAXN][logn];
int tin[MAXN], tout[MAXN], used[MAXN];
int timer = 0;
vector<int> g[MAXN];

void dfs(int v, int p) {
    up[v][0] = p;
    used[v] = 1;
    for (int i = 1; i < logn; i++) {
        up[v][i] = up[up[v][i - 1]][i - 1];
    }
    tin[v] = timer++;
    for (auto k : g[v]) {
        if (k != p) dfs(k, v);
    }
    tout[v] = timer;
}

bool ancestor(int u, int v) { // u -> v
    return tin[u] <= tin[v] && tout[u] >= tout[v];
}

int lca(int u, int v) {
    if (ancestor(u, v)) return u;
    if (ancestor(v, u)) return v;
    for (int i = logn - 1; i >= 0; i--) {
        if (!ancestor(up[v][i], u)) v = up[v][i];
    }
    return up[v][0];
}

signed main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    cin >> n >> m;
    int x, y, z, a1, a2;
    for (int i = 0; i < MAXN; i++) used[i] = 0;
    for (int i = 1; i < n; i++) {
        cin >> x;
        g[i].pb(x);
        g[x].pb(i);
    }
    cin >> a1 >> a2 >> x >> y >> z;
    int lst = 0, a3, a4;
    for (int i = 0; i < n; i++) {
        if (!used[i]) {
            dfs(i, i);
        }
    }
    int ans = 0;
    for (int i = 0; i < m; i++) {
        lst = lca((a1 + lst) % n, a2);
        ans += lst;
        a3 = (x * a1 + y * a2 + z) % n;
        a4 = (x * a2 + y * a3 + z) % n;
        a1 = a3;
        a2 = a4;
    }
    cout << ans;
}
/*
*/