Find The Location of Sub-string (Algorithm 3.3)

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/**Bismillahir Rahmanir Rahim.**/

#include <stdio.h>
#include <string.h>
int main()
{
    char t[1000], p[1000];
    int k, r, s, Index = -1, max, l, m, cnt;
    printf("Please, Input string.\n");
    s = strlen(gets(t));
    printf("Please, Input Sub-string.\n");
    r = strlen(gets(p));
    max = s-r+1;
    for(k=0; k<max; k++)
    {
        if(t[k]==p[0])
        {
            for(l=1, cnt=1, m=k+1; l<r; l++, m++)
            {
                if(p[l]==t[m])
                    cnt++;
                else break;
            }
            if(cnt==r)
            {
                Index = k;
                printf("INDEX = %d\n", Index);
                k+=(r-1);
            }
        }
    }
    if(Index==-1) printf("There is no matching\n");
    return 0;
}