Package g0901_1000.s0927_three_equal_parts

Class Solution

  • public class Solution
extends Object
    927 - Three Equal Parts.

    Hard

    You are given an array arr which consists of only zeros and ones, divide the array into three non-empty parts such that all of these parts represent the same binary value.

    If it is possible, return any [i, j] with i + 1 < j, such that:

    • arr[0], arr[1], ..., arr[i] is the first part,
    • arr[i + 1], arr[i + 2], ..., arr[j - 1] is the second part, and
    • arr[j], arr[j + 1], ..., arr[arr.length - 1] is the third part.
    • All three parts have equal binary values.

    If it is not possible, return [-1, -1].

    Note that the entire part is used when considering what binary value it represents. For example, [1,1,0] represents 6 in decimal, not 3. Also, leading zeros are allowed , so [0,1,1] and [1,1] represent the same value.

    Example 1:

    Input: arr = [1,0,1,0,1]

    Output: [0,3]

    Example 2:

    Input: arr = [1,1,0,1,1]

    Output: [-1,-1]

    Example 3:

    Input: arr = [1,1,0,0,1]

    Output: [0,2]

    Constraints:

    • 3 <= arr.length <= 3 * 104
    • arr[i] is 0 or 1

    • Constructor Detail

      • Solution

        public Solution()

    • Method Detail

      • threeEqualParts

        public int[] threeEqualParts​(int[] arr)