Problem: Isomorphic Strings

Statement

Given two strings s and t, determine whether they are isomorphic.

Two strings are considered isomorphic if there exists a one-to-one mapping from every character in s to a character in t such that replacing each character in s according to this mapping produces t. The mapping must preserve character order. Every occurrence of a given character in s must map to the same character in t, and no two distinct characters in s may map to the same character in t. A character is allowed to map to itself.

Return TRUE if s and t are isomorphic, and FALSE otherwise.

Note: The mapping must be bijective, meaning it is both one-to-one (no two characters in s map to the same character in t) and consistent (each character in s always maps to the same character in t).

Constraints:

• $1 \leq$ s.length $\le 5\times 10^4$ ...