Single Number

Single Number - InterviewBitInterviewBit

Given an array of integers A, every element appears twice except for one. Find that single one.

Thoughts

• 0:00 The name is giving me no hint about what the question is about. Let's see how much time it will take.

• 0:35 Solved it in 35 seconds. I missed superman though as I was too excited to write the time in these notes. DONE

int Solution::singleNumber(const vector<int> &A) {
    int res = 0;
    for(int x: A)
        res = res ^ x;
    return res;
}

Time Complexity: $O(n)$​

Space Complexity: $O(1)$​