An expression contains only 3 kinds of brackets (Round brackets, Curly, Square brackets). Write a Pseudocode to determine if the expression is valid.

Eg :

Input: = "()[]{}" Output: true 

Input: = "(]" Output: false

An expression is valid if:

Open brackets must be closed by the same type of brackets.

Open brackets must be closed in the correct order.

Every close bracket has a corresponding open bracket of the same type.