C++ Program to Perform Naive String Matching

#include<stdio.h>
#include<string.h>
void search(char *pat, char *txt)
{
    int M = strlen(pat);
    int N = strlen(txt);
 
    /* A loop to slide pat[] one by one */
    for (int i = 0; i <= N - M; i++)
    {
        int j;
 
        /* For current index i, check for pattern match */
        for (j = 0; j < M; j++)
        {
            if (txt[i + j] != pat[j])
                break;
        }
        if (j == M) // if pat[0...M-1] = txt[i, i+1, ...i+M-1]
        {
            printf("Pattern found at index %d \n", i);
        }
    }
}
 
/* Driver program to test above function */
int main()
{
    char *txt = "AABAACAADAABAAABAA";
    char *pat = "AABA";
    search(pat, txt);
    return 0;
}

Output:

Pattern found at index 0 
Pattern found at index 9 
Pattern found at index 13 
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