Package g1601_1700.s1664_ways_to_make_a_fair_array

Class Solution

  • public class Solution
extends Object
    1664 - Ways to Make a Fair Array.

    Medium

    You are given an integer array nums. You can choose exactly one index ( 0-indexed ) and remove the element. Notice that the index of the elements may change after the removal.

    For example, if nums = [6,1,7,4,1]:

    • Choosing to remove index 1 results in nums = [6,7,4,1].
    • Choosing to remove index 2 results in nums = [6,1,4,1].
    • Choosing to remove index 4 results in nums = [6,1,7,4].

    An array is fair if the sum of the odd-indexed values equals the sum of the even-indexed values.

    Return the number of indices that you could choose such that after the removal, nums is fair.

    Example 1:

    Input: nums = [2,1,6,4]

    Output: 1

    Explanation:

    Remove index 0: [1,6,4] -> Even sum: 1 + 4 = 5. Odd sum: 6. Not fair.

    Remove index 1: [2,6,4] -> Even sum: 2 + 4 = 6. Odd sum: 6. Fair.

    Remove index 2: [2,1,4] -> Even sum: 2 + 4 = 6. Odd sum: 1. Not fair.

    Remove index 3: [2,1,6] -> Even sum: 2 + 6 = 8. Odd sum: 1. Not fair.

    There is 1 index that you can remove to make nums fair.

    Example 2:

    Input: nums = [1,1,1]

    Output: 3

    Explanation: You can remove any index and the remaining array is fair.

    Example 3:

    Input: nums = [1,2,3]

    Output: 0

    Explanation: You cannot make a fair array after removing any index.

    Constraints:

    • 1 <= nums.length <= 105
    • 1 <= nums[i] <= 104

    • Constructor Detail

      • Solution

        public Solution()

    • Method Detail

      • waysToMakeFair

        public int waysToMakeFair​(int[] nums)