def count_ocurrency(txt, pat) -> int:
    s = len(txt)
    x = len(pat)
    count = 0
    for i in range(s - x + 1):
        j = 0
        for n in range(x):
            if txt[i + n] != pat[n]:
                break
            j +=1

        if  j == x:
            count += 1
            
    return count
        

print(count_ocurrency("abac", "abbc"))