1304-find-n-unique-integers-sum-up-to-zero.py

"""
Problem Link: https://leetcode.com/problems/find-n-unique-integers-sum-up-to-zero/

Given an integer n, return any array containing n unique integers such that they add up to 0.

Example 1:
Input: n = 5
Output: [-7,-1,1,3,4]
Explanation: These arrays also are accepted [-5,-1,1,2,3] , [-3,-1,2,-2,4].

Example 2:
Input: n = 3
Output: [-1,0,1]

Example 3:
Input: n = 1
Output: [0]
 
Constraints:
1 <= n <= 1000
"""
class Solution:
    def sumZero(self, n: int) -> List[int]:
        res = []
        if n % 2 != 0:
          res.append(0)
          n -= 1
        n //= 2
        for i in range(1, n+1):
          res.extend([-i, i])
        
        return res

"""
n = 1, [0]
n = 2, [-1, 1]
n = 3, [-2, 0, 2]
n = 4, [-3, -1, 1, 3]
n = 5, [-4, -2, 0, 2, 4]

Explanation
Find the rule
A[i] = i * 2 - n + 1
"""
class Solution1:
    def sumZero(self, n: int) -> List[int]:
        return [i for i in range(1 - n, n, 2)]