#include <bits/stdc++.h>

using namespace std;
const int INF = 2'100'000'000;

void count_heights(int now, vector<std::vector<int>> &m_adj, vector<bool> &visited,
              vector<int> &heights, vector<int> &ancestors) {
    visited[now] = true;
    if (now == 0) {
        heights[now] = 0;
    } else {
        heights[now] = heights[ancestors[now]] + 1;
    }
    for (auto neig : m_adj[now]) {
        if (!visited[neig]) {
            count_heights(neig, m_adj, visited, heights, ancestors);
        }
    }
}

void balance_h(int &v_first, int &v_second, const vector<int> &heights, const vector<int> &ancestors) {
    if (heights[v_first] == heights[v_second]) {
        return;
    }
    if (heights[v_first] > heights[v_second]) {
        while (heights[v_first] != heights[v_second]) {
            v_first = ancestors[v_first];
        }
    } else {
        balance_h(v_second, v_first, heights, ancestors);
    }

}

int LCA(int v_first, int v_second,
        vector<vector<int>> &up,
        const vector<int> &ancestors,vector<int>&heights) {
    balance_h(v_first, v_second,heights,ancestors);
    if (v_first == v_second) {
        return v_first;
    }
    int k = up.size() - 1;
    while (k >= 0) {
        if (up[k][v_first] != up[k][v_second]) {
            v_first = up[k][v_first];
            v_second = up[k][v_second];
        }
        --k;
    }
    if (v_first == v_second) {
        return v_first;
    }
    return ancestors[v_first];
}

int main() {
    int N, M;
    cin >> N >> M;
    vector<int> arr(N);
    vector<int> ancestors(N, -1);
    ancestors[0] = -1;
    vector<vector<int>> m_adj;
    m_adj.resize(N);
    vector<bool> visited(N, false);
    for (int i = 1; i < N; ++i) {
        cin >> arr[i];
        ancestors[i] = arr[i];
        m_adj[arr[i]].push_back(i);
        m_adj[i].push_back(arr[i]);
    }
    vector<int> heights(N);
    count_heights(0, m_adj, visited, heights, ancestors);
    int max_degree = 0;
    while (pow(2, max_degree + 1) < N) {
        ++max_degree;
    }
    vector<vector<int>> up(max_degree + 1, vector<int>(N, 0));
    up[0][0] = -1;
    for (int el = 1; el < N; ++el) {
        up[0][el] = ancestors[el];
    }
    for (int i = 1; i <= max_degree; ++i) {
        for (int el = 1; el < N; ++el) {
            if (up[i - 1][el] == -1) {
                up[i][el] = -1;
            } else {
                up[i][el] = up[i - 1][up[i - 1][el]];
            }
        }
    }
    int a_first, a_second;
    cin >> a_first >> a_second;
    int x, y, z;
    cin >> x >> y >> z;
    int sum_ = 0;
    int a_third = a_first;
    int a_fouth = a_second;
//    balance_h(a_third, a_fouth, heights, ancestors);
    int last_ans = LCA(a_third, a_fouth, up, ancestors,heights);
    sum_ += last_ans;
    for (int i = 2; i <= M; ++i) {
        a_first = (x * a_third + y * a_fouth + z) % N;
        a_second = (x * a_fouth + y * a_first + z) % N;
        a_third = a_first;
        a_fouth = a_second;
//        balance_h(query_first, query_second, heights, ancestors);
        last_ans = LCA((a_first + last_ans) % N, a_second, up, ancestors,heights);
        sum_ += last_ans;
    }
    cout << sum_;
}