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
SOLUTION:
class Solution:
    def sumZero(self, n: int) -> List[int]:
        if n == 1:
            return [0]
        if n == 2:
            return [-1, 1]
        prev = self.sumZero(n - 2)
        return [prev[0] - 1] + prev + [prev[-1] + 1]

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