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#include <bits/stdc++.h>
using namespace std;
ifstream f("strmatch.in");
ofstream g("strmatch.out");
string pat, txt;
vector<int> rez;
void computeLPSArray(int M, int *lps);
// Prints occurrences of txt[] in pat[]
void KMPSearch()
{
int M = pat.size();
int N = txt.size();
// create lps[] that will hold the longest prefix suffix
// values for pattern
int lps[M];
// Preprocess the pattern (calculate lps[] array)
computeLPSArray(M, lps);
int i = 0; // index for txt[]
int j = 0; // index for pat[]
while (i < N)
{
if (pat[j] == txt[i])
{
j++;
i++;
}
if (j == M)
{
rez.push_back(i - j);
j = lps[j - 1];
}
// mismatch after j matches
else if (i < N && pat[j] != txt[i])
{
// Do not match lps[0..lps[j-1]] characters,
// they will match anyway
if (j != 0)
j = lps[j - 1];
else
i = i + 1;
}
}
}
// Fills lps[] for given patttern pat[0..M-1]
void computeLPSArray(int M, int *lps)
{
// length of the previous longest prefix suffix
int len = 0;
lps[0] = 0; // lps[0] is always 0
// the loop calculates lps[i] for i = 1 to M-1
int i = 1;
while (i < M)
{
if (pat[i] == pat[len])
{
len++;
lps[i] = len;
i++;
}
else // (pat[i] != pat[len])
{
// This is tricky. Consider the example.
// AAACAAAA and i = 7. The idea is similar
// to search step.
if (len != 0)
{
len = lps[len - 1];
// Also, note that we do not increment
// i here
}
else // if (len == 0)
{
lps[i] = 0;
i++;
}
}
}
}
// Driver program to test above function
int main()
{
f >> pat >> txt;
KMPSearch();
g << rez.size() << '\n';
for (int i = 0; i < min(int(rez.size()), 1000); i++)
g << rez[i] << ' ';
return 0;
}