Watch 10 video solutions for Three Equal Parts, a hard level problem involving Array, Math. This walkthrough by Stationery Pal has 8,563,230 views views. Want to try solving it yourself? Practice on FleetCode or read the detailed text solution.
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, andarr[j], arr[j + 1], ..., arr[arr.length - 1] is the third part.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 * 104arr[i] is 0 or 1