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#include<cstdio>
#include<algorithm>
#include "message.h"
#include "poszukiwania.h"
#include<utility>
#include<iostream>

typedef unsigned long long int ll;

using namespace std;

int s,m, myNum, non;

const ll p=1063;     // a small prime number
const ll q=(1ULL<<61)-1;  // a big prime number

const ll mask = (1ULL << 32) - 1;

ll modq(ll x) { // x % q
    // x = 2^61 * (x >> 61) + x mod 2^61
    return (x >> 61) + (x & q);
}

ll mod32q(ll x) { // 2^32 * x % q
    // x = 2^29 * (x >> 29) + x mod 2^29
    // 2^32 * x = 2^61 * (x >> 29) + (x mod 2^29) << 32
    return (x >> 29) + ( (x & ((1 << 29) - 1)) << 32 );
}

ll mul(ll a, ll b) {
    // 2^61 = 1
    // a = a1 a0, b = b1 b0, a * b = 2^64 * a1 * b1 + 2^32 * (a1 * b0 + a0 * b1) + a0 * b0
    // = 2^3 * mod(a1 * b1)
    ll a0 = a & mask;
    ll a1 = a >> 32;
    ll b0 = b & mask;
    ll b1 = b >> 32;
    return (modq(modq(a1 * b1) << 3) + mod32q(a1 * b0) + mod32q(a0 * b1) + modq(a0 * b0)) % q;
}

// tu moznaby dac szybkie potegowanie ale
// i tak kazdy procek poteguje ze trzy razy tylko
ll power(ll p, ll i) {
    if (i == 0)
        return 1;
    ll p2 = power(p, i / 2);
    ll result = mul(p2, p2);
    if (i & 1)
        result = mul(result, p);
    return result;
}

ll slowpower(ll p, ll i) {
    ll result=1;
    for(int j=0; j<i; ++j) result=mul(result,p);
    return result;
}

ll HashS() {
   int intLen=s/non+1;
   int myIntBegin=myNum*intLen; ll h=0;
   for(int i = min(myIntBegin+intLen,s)-1; i >= myIntBegin;--i) {
       h=mul(h,p);
       h=(h+SignalAt(i+1))%q;
   }
   ll hPref=h;
   if(myNum!=0) {
      int instance = Receive(myNum-1);
      ll hash_prev=GetLL(instance);
      hPref=(hash_prev+mul(power(p,myIntBegin),h))%q;
   }

   if(myNum!=non-1) {
      PutLL(myNum+1,hPref);
      Send(myNum+1);

      int instance = Receive(non-1);
      hPref=GetLL(instance);
   }
   // w tym momencie non-1 ma hash sygnalu
   else
      for(int i=0; i<non-1; ++i) {
          PutLL(i,hPref);
          Send(i);
      }
   return hPref;
}

pair<ll,ll> HashMSuff() {
   int intLen=m/non+1;
   int r=(s-1)%intLen;
   int myIntBegin=myNum*intLen; ll h=0; ll hr=0;
   for(int i = min(myIntBegin+intLen,m)-1; i >= myIntBegin;--i) {
       h=mul(h,p);
       h=(h+SeqAt(i+1))%q;
       //cout << i << " , " << h << endl;
       if(i==myIntBegin+r) hr=h;
   }

   //cout << "hr = " << hr << "   my piece = " << h << endl;
   ll hSuff=h;
   ll hash_next=0;
   if(myNum!=non-1) {
      int instance = Receive(myNum+1);
      hash_next=GetLL(instance);
      hSuff=(mul(hash_next,power(p,intLen))+h)%q;
      hr=(mul(hash_next,power(p,intLen-r))+hr)%q;
   }
   if(myNum!=0) {
      PutLL(myNum-1,hSuff);
      Send(myNum-1);
   }

   return pair<ll,ll>(hr, hash_next);
}


int main() {
   s=SignalLength();
   m=SeqLength();
   non=NumberOfNodes();
   myNum=MyNodeId();

   // kazdy sie dowiaduje jaki jest hash sygnalu
   ll signal_h=HashS();

   pair<ll,ll> suffPair=HashMSuff();
   ll hr=suffPair.first;
   ll hash_next=suffPair.second;

   int intLen=m/non+1;
   int r=(s-1)%intLen;
   int myIntBegin=myNum*intLen;

   if(myIntBegin+r >= s) {
      int address=(myIntBegin+r-s)/intLen;
      PutLL(address,hr);
      Send(address);
   }

   ll hr_next=0;
   if(myIntBegin+intLen-1+s < non*intLen) { // jesli spodziewamy sie wiadomosci
      int instance = Receive((myIntBegin+intLen-1+s)/intLen);
      hr_next=GetLL(instance);
   }
   int counter=0; ll pp=power(p,s);
   for(int i=min(m,myIntBegin+intLen)-1; i>=myIntBegin; --i) {
      hash_next=(mul(hash_next,p)+SeqAt(i+1))%q;
      if(i+s <= m) {  // znaczy miescimy sie
          if(hash_next == (signal_h + mul(hr_next,pp))%q ) counter++;
          hr_next=(mul(hr_next,p) + SeqAt(i+s))%q;
      }
   }

   // zbieranie wyników
   if(myNum!=0) {
       PutInt(0,counter);
       Send(0);
   }
   else {
      int result=counter;
      for(int i=1; i<non; ++i) {
          int instance=Receive(i);
          result += GetInt(instance);
      }
      printf("%d",result);
   }
   return 0;
}