2574. Left and Right Sum Differences

题目 #

Given a 0-indexed integer array nums, find a 0-indexed integer array answer where:

  • answer.length == nums.length.
  • answer[i] = |leftSum[i] - rightSum[i]|.

Where:

  • leftSum[i] is the sum of elements to the left of the index i in the array nums. If there is no such element, leftSum[i] = 0.
  • rightSum[i] is the sum of elements to the right of the index i in the array nums. If there is no such element, rightSum[i] = 0.

Return the array answer.

Example 1:

Input: nums = [10,4,8,3]
Output: [15,1,11,22]
Explanation: The array leftSum is [0,10,14,22] and the array rightSum is [15,11,3,0].
The array answer is [|0 - 15|,|10 - 11|,|14 - 3|,|22 - 0|] = [15,1,11,22].

Example 2:

Input: nums = [1]
Output: [0]
Explanation: The array leftSum is [0] and the array rightSum is [0].
The array answer is [|0 - 0|] = [0].

Constraints:

  • 1 <= nums.length <= 1000
  • $1 <= nums[i] <= 10^5$

思路1 #

分析 #

  • 照着做

代码 # 

 1func abs(a int) int {
 2	if a < 0 {
 3		return -a
 4	}
 5	return a
 6}
 7
 8func leftRigthDifference(nums []int) []int {
 9	result := make([]int, len(nums))
10	rsum := 0
11	for _, v := range nums {
12		rsum += v
13	}
14	lsum := 0
15	for i, v := range nums {
16		rsum -= v
17		result[i] = abs(lsum - rsum)
18		lsum += v
19	}
20	return result
21}