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#include "poszukiwania.h"
#include "message.h"

#include <algorithm>
#include <iostream>
#include <vector>
#include <utility>

using namespace std;

#define PB push_back
#define ST first
#define ND second
#define MP make_pair

typedef long long LL;

LL N, M, B;
int Bb, Be;
int my_id, nodes;

LL CeilDiv(LL a, LL b)
{
    return (a + b - 1) / b;
}

vector<int> pi; // For KMP algorighm
vector<int> matches;

void KMPPrefix()
{
    int k = -1;
    pi.PB(-1);
    for (int q = Bb; q < Be; ++q) {
        while (k >= 0 && SignalAt(Bb + k + 1 + 1) != SignalAt(q + 1))
            k = pi[k];

        if (SignalAt(Bb + k + 1 + 1) == SignalAt(q + 1))
            ++k;

        pi.PB(k);
    }
}

void SearchForSignal()
{
    KMPPrefix();
    int q = -1;
    int m = Be - Bb;
    for (int i = Bb; i < N - (M - Be); ++i) {
        while (q >= 0 && SignalAt(Bb + q + 1 + 1) != SeqAt(i + 1))
            q = pi[q];

        if (SignalAt(Bb + q + 1 + 1) == SeqAt(i + 1))
            ++q;

        //if (i - Bb > m && q <= i - Bb - m + 1)
        //    break;

        if (q == m - 1) {
            matches.PB(i - Bb - m + 1);
            q = pi[q];
        }
    }

    //cerr << "matches: |" << matches.size() << "|";
    //for (auto m: matches) cerr << " " << m;
    //cerr << endl;
}

void FilterMatches(int p, vector<int>& mch)
{
    mch.clear();
    Receive(p);
    int n = GetInt(p);
    for (int i = 0; i < n; ++i) {
        int m = GetInt(p);
        if (binary_search(begin(matches), end(matches), m))
            mch.PB(m);
    }
}

void SendMatches(int nd, const vector<int>& mch)
{
    PutInt(nd, (int) mch.size());
    for (auto v: mch)
        PutInt(nd, v);
    Send(nd);
}

void MergeResults()
{
    std::vector<int> mch;
    int an = CeilDiv(M, B);

    while (an >= 2) {
        int an2 = CeilDiv(an, 2);
        if (my_id >= an2) {
            SendMatches(my_id - an2, matches);
            return;
        } else if (my_id + an2 < an) {
            FilterMatches(my_id + an2, mch);
            swap(matches, mch);
        }

        an = an2;
    }
    cout << matches.size() << "\n";
}


int main()
{
  N = SeqLength();
  M = SignalLength();
  my_id = MyNodeId();
  nodes = NumberOfNodes();
  B = CeilDiv(M, nodes);
  Bb = (int)(my_id * B);
  Be = (int)min((my_id + 1) * B, M);

  if (Bb >= Be) return 0;

  SearchForSignal();
  MergeResults();

  return 0;
}