# ---
# title: 342. Power of Four
# id: problem342
# author: Tian Jun
# date: 2020-10-31
# difficulty: Easy
# categories: Bit Manipulation
# link: <https://leetcode.com/problems/power-of-four/description/>
# hidden: true
# ---
# 
# Given an integer `n`, return _`true` if it is a power of four. Otherwise,
# return `false`_.
# 
# An integer `n` is a power of four, if there exists an integer `x` such that `n
# == 4x`.
# 
# 
# 
# **Example 1:**
# 
#     
#     
#     Input: n = 16
#     Output: true
#     
# 
# **Example 2:**
# 
#     
#     
#     Input: n = 5
#     Output: false
#     
# 
# **Example 3:**
# 
#     
#     
#     Input: n = 1
#     Output: true
#     
# 
# 
# 
# **Constraints:**
# 
#   * `-231 <= n <= 231 - 1`
# 
# 
# 
# **Follow up:** Could you solve it without loops/recursion?
# 
# 
## @lc code=start
using LeetCode

## add your code here:
## @lc code=end
