Neighboring Bitwise XOR Solution in Java

Explore Solutions in Other Languages

Problem Description

Welcome to the world of XOR, where bits dance around like they’re at a party, and the only rule is: “If you have two of the same, they cancel each other out!” The problem at hand is like trying to figure out if your friends can form a circle without anyone standing awkwardly alone.

In the Neighboring Bitwise XOR problem, you are given an array called derived, which is formed by taking the XOR of neighboring elements from an original array original. Your task is to determine if there exists an original array such that the XOR of all elements in derived equals zero.

Imagine you’re at a party, and you want to know if everyone can hold hands in a circle without leaving anyone out. If the XOR of all the derived hand-holding pairs equals zero, then yes, they can! If not, well, someone’s going home alone.

Code Solution


class Solution {
  public boolean doesValidArrayExist(int[] derived) {
    return Arrays.stream(derived).reduce((a, b) -> a ^ b).getAsInt() == 0;
  }
}

Approach Explanation

The approach here is straightforward yet clever. The code uses the XOR operation to reduce the derived array into a single integer. If the result is zero, it means that the original array can exist, as all pairs of XORs have canceled each other out. It’s like checking if all your friends can hold hands without anyone being left out!

Time and Space Complexity

Complexity Type	Complexity
Time Complexity	O(n)
Space Complexity	O(1)

Real-World Example

Let’s say you have a group of friends who are trying to form a circle for a group photo. Each friend can either hold hands with their neighbor or not. If everyone can hold hands in such a way that no one is left out (i.e., the XOR of their hand-holding pairs equals zero), then you can take that perfect group photo! If not, well, someone’s going to be awkwardly standing off to the side.