Dev Tools · 1h ago
Master the XOR Trick: Find the Unique Element in an Array
The XOR operation's properties allow finding the single non-duplicate element in an array in O(n) time with O(1) space. By XORing all elements, pairs cancel out (a ^ a = 0), leaving the unique value. This technique is a classic coding interview solution that avoids extra memory.
Meridian48 take
The article frames XOR as a 'trick,' but it's a fundamental bitwise pattern every developer should know—not a secret move.
bitwise-operationscoding-interviews