LC daily

divi-259 · divi-259 · commit 1942a4f235d2 · 2023-10-31T14:42:25.000-07:00
diff --git a/Daily LC/31_Oct_2023_Find_the_Original_array_of_Prefix_xor.java b/Daily LC/31_Oct_2023_Find_the_Original_array_of_Prefix_xor.java
@@ -0,0 +1,42 @@
+/*
+Problem Link: https://leetcode.com/problems/find-the-original-array-of-prefix-xor/description/
+
+Problem Statement: You are given an integer array pref of size n. Find and return the array arr of size n that satisfies:
+
+pref[i] = arr[0] ^ arr[1] ^ ... ^ arr[i].
+Note that ^ denotes the bitwise-xor operation.
+
+It can be proven that the answer is unique.
+
+Solution Approach: 
+A XOR B = C
+A XOR C = B
+the above property will only work in the context of writing a program.
+Using this property we can calculate the ans array
+
+*/
+
+/* ------------CODE---------------- */
+class Solution {
+    public int[] findArray(int[] pref) {
+
+        int n = pref.length;
+        int arr[] = new int[n];
+
+        arr[0] = pref[0];
+
+        // pref[1] = arr[0]^arr[1]
+        int xor = arr[0];
+        for(int i=1; i<n; i++) {
+            arr[i] = pref[i]^xor;
+            xor = xor^arr[i];
+        }
+        return arr;
+        
+    }
+}
+
+/*
+Time Complexity: O(n)
+Space Complexity: O(n)
+*/
