### Decode XORed Array LeetCode Solution - The Coding Shala

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In this post, we will learn how to solve LeetCode's Decode XORed Array Problem and will implement its solution in Java.

## Decode XORed Array Problem

There is a hidden integer array arr that consists of n non-negative integers. It was encoded into another integer array encoded of length n - 1, such that encoded[i] = arr[i] XOR arr[i + 1]. For example, if arr = [1,0,2,1], then encoded = [1,2,3]. You are given the encoded array. You are also given an integer first, that is the first element of arr, i.e. arr.
Return the original array arr. It can be proved that the answer exists and is unique.

Example 1:
Input: encoded = [1,2,3], first = 1
Output: [1,0,2,1]
Explanation: If arr = [1,0,2,1], then first = 1 and encoded = [1 XOR 0, 0 XOR 2, 2 XOR 1] = [1,2,3]

## LeetCode - Decode XORed Array Java Solution

Approach 1

For example, a ^ b = c, where c is given, and the first element(a) is also given. If we do a ^ c then we will get b, our second element in the output array.

Java Program:

```class Solution {
public int[] decode(int[] encoded, int first) {
int size = encoded.length;
int[] res = new int[size+1];
res = first;
for(int i=0; i<size; i++) {
res[i+1] = res[i] ^ encoded[i];
}
return res;
}
}
```

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