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/*
Following program is a C++ implementation of Rabin Karp
Algorithm given in the CLRS book
*/
#include <bits/stdc++.h>
using namespace std;
ifstream fin ("strmatch.in");
ofstream fout ("strmatch.out");
queue<int> Coada;
int cont;
// d is the number of characters in the input alphabet
#define d 256
/*
pat -> pattern
txt -> text
q -> A prime number
*/
void search(char pat[], char txt[], int q)
{
int M = strlen(pat);
int N = strlen(txt);
int i, j;
int p = 0; // hash value for pattern
int t = 0; // hash value for txt
int h = 1;
// The value of h would be "pow(d, M-1)%q"
for (i = 0; i < M - 1; i++)
h = (h * d) % q;
// Calculate the hash value of pattern and first window of text
for (i = 0; i < M; i++) {
p = (d * p + pat[i]) % q;
t = (d * t + txt[i]) % q;
}
// Slide the pattern over text one by one
for (i = 0; i <= N - M; i++) {
// Check the hash values of current window of text and pattern.
// If the hash values match, then only check for characters one by one
if (p == t) {
/* Check for characters one by one */
for (j = 0; j < M; j++) {
if (txt[i + j] != pat[j]) {
break;
}
}
// if p == t and pat[0...M-1] = txt[i, i+1, ...i+M-1]
if (j == M)
{
cont++;
Coada.push(i);
// fout << "Pattern found at index " << i << endl;
}
}
// Calculate hash value for next window of text:
// Remove leading digit, add trailing digit
if (i < N - M) {
t = (d * (t - txt[i] * h) + txt[i + M]) % q;
// We might get negative value of t, converting it to positive
if (t < 0)
t = (t + q);
}
}
}
int main()
{
char txt[2000000], pat[2000000];
fin >> pat >> txt;
// we mod to avoid overflowing of value but we should take as big q as possible to avoid the collison
int q = INT_MAX;
// Function Call
search(pat, txt, q);
fout << cont << "\n";
while(!Coada.empty())
{
fout << Coada.front() << " ";
Coada.pop();
}
return 0;
}