712544. Maximum XOR With an Element From Array
Hard
Maximum XOR With an Element From Array
Summary
The problem involves finding the maximum possible XOR value that can be obtained by performing a bitwise XOR operation with each element in an array, given another target element. The goal is to maximize the sum of all these XOR values.
Detailed Explanation
We can solve this problem by iterating through each element in the array and calculating the XOR value with the target element. We keep track of the maximum XOR value seen so far. This approach has a time complexity of O(n), where n is the size of the array, since we need to iterate through all elements.
Here's a step-by-step breakdown:
- Initialize a variable
max_xorto 0. - Iterate through each element
xin the array:- Calculate the XOR value
xor_valbetweenxand the target element. - Update
max_xorifxor_valis greater thanmax_xor.
- Calculate the XOR value
- Return
max_xor.
Time complexity: O(n) Space complexity: O(1)
Here's an ASCII art diagram to illustrate this:
+---------------+
| Array [a, b, c] |
+---------------+
| Target |
| element (t) |
+---------------+
| XOR (a, t) = a^t|
| XOR (b, t) = b^t|
| ...
| max_xor = max(a^t, b^t, ...)|
+---------------+
Optimized Solutions
Java
public class Solution {
public int findMaximumXOR(int[] nums, int target) {
int max_xor = 0;
for (int num : nums) {
int xor_val = num ^ target;
if (xor_val > max_xor) {
max_xor = xor_val;
}
}
return max_xor;
}