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/* Following program is a C++ implementation of Rabin Karp
Algorithm given in the CLRS book */
#include <fstream>
#include <cstring>
using namespace std;
ifstream cin("strmatch.in");
ofstream cout("strmatch.out");
// d is the number of characters in the input alphabet
#define d 256
char s1[2000001];
char s2[2000001];
int v[2000001];
int nr=0;
/* 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 )
{
bool flag = true;
/* Check for characters one by one */
for (j = 0; j < M; j++)
{
if (txt[i+j] != pat[j])
{
flag = false;
break;
}
}
// if p == t and pat[0...M-1] = txt[i, i+1, ...i+M-1]
if (j == M){
nr++;
v[i]=1;
}
}
// 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);
}
}
}
/* Driver code */
int main()
{
cin.get(s1,2000001);
cin.get();
cin.get(s2,2000001);
if(strlen(s1)>strlen(s2)){
cout<<"0";
return 0;
}
// A prime number
int q = 101;
// Function Call
search(s1, s2, q);
cout<<nr<<endl;
nr=0;
for(int i=0;i<=strlen(s2) && nr<1000;i++)
{
if(v[i]) cout<<i<<" ";
nr++;
}
cin.close();
cout.close();
return 0;
}
// This is code is contributed by rathbhupendra