[LeetCode]#1304. Find N Unique Integers Sum up to Zero

Environment: Python 3.7

Key technique: //, %

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

Analysis:

1. If n is even, add 1, -1, 2, -2…..
2. If n is odd, follow even rule and add 0 in last location.

Solution:

class Solution:
    def sumZero(self, n):
        ans=[]
        for i in range(1,n//2+1):
            ans.append(i)
            ans.append(-i)
        if n % 2 !=0:
            ans.append(0)
        return ans