2156. Find Substring With Given Hash Value

The hash of a 0-indexed string s of length k, given integers p and m, is computed using the following function: - hash(s, p, m) = (val(s[0]) * p0 + val(s[1]) * p1 + ... + val(s[k-1]) * pk-1) mod m. Where val(s[i]) represents the index of s[i] in the alphabet from val('a') = 1 to val('z') = 26. You are given a string s and the integers power, modulo, k, and hashValue. Return sub, the first subst