$ cat ./coding/367-valid-perfect-square.md

────────────────────────────────────────────────────────────

367. Valid Perfect Square

class Solution:
    def isPerfectSquare(self, num: int) -> bool:  
        if num == 1:
            return True
        left = 1
        right = num // 2

        while left <= right:
            mid = left + (right - left) // 2
            square = mid * mid
            if square == num:
                return True
            elif square > num:
                right = mid - 1
            elif square < num:
                left = mid + 1

        return False

$ ls ./coding/ | grep -v 367-valid-perfect-square