# Question

Formatted question description: https://leetcode.ca/all/367.html

 367	Valid Perfect Square

Given a positive integer num, write a function which returns True if num is a perfect square else False.

Note: Do not use any built-in library function such as sqrt.

Example 1:

Input: 16
Returns: True

Example 2:

Input: 14
Returns: False


# Algorithm

Search from 1 to sqrt(num) to see if there is a number whose square is exactly equal to num.

Java