1061. Lexicographically Smallest Equivalent String

You are given two strings of the same length s1 and s2 and a string baseStr. We say s1[i] and s2[i] are equivalent characters. - For example, if s1 = "abc" and s2 = "cde", then we have 'a' == 'c', 'b' == 'd', and 'c' == 'e'. Equivalent characters follow the usual rules of any equivalence relation: - Reflexivity: 'a' == 'a'. - Symmetry: 'a' == 'b' implies 'b' == 'a'. - Transitivity: 'a' == 'b