public class Solution
extends Object
473 - Matchsticks to Square\.
Medium
You are given an integer array `matchsticks` where `matchsticks[i]` is the length of the ith matchstick. You want to use **all the matchsticks** to make one square. You **should not break** any stick, but you can link them up, and each matchstick must be used **exactly one time**.
Return `true` if you can make this square and `false` otherwise.
**Example 1:**
**Input:** matchsticks = [1,1,2,2,2]
**Output:** true
**Explanation:** You can form a square with length 2, one side of the square came two sticks with length 1.
**Example 2:**
**Input:** matchsticks = [3,3,3,3,4]
**Output:** false
**Explanation:** You cannot find a way to form a square with all the matchsticks.
**Constraints:**
* `1 <= matchsticks.length <= 15`
* 1 <= matchsticks[i] <= 108