naive pattern matching in c

#include <stdio.h>


int patternMatching(char txt[], char pt[]){

    int n = strlen(txt);
    int m = strlen(pt);

    int i, j;

    int index = -1;


    for(i=0; i<=(n-m); i++){

        for(j=0; j<m; j++){
            if(txt[i+j]!=pt[j])break;
        }

        if(j==m){
            index = i;
            break;
        }

    }

    return index;

}


int main()
{
    char text[30];
    char pat[30];

    printf("Enter text: ");
    gets(text);
    printf("Enter pattern: ");
    gets(pat);

    int pos = patternMatching(text, pat);

    if(pos==-1){
        printf("Pattern not found!");
    }
    else{
        printf("Pattern found at position %d\n", pos+1);
    }





}