136. Single Number.md

Solution1

class Solution {
    public int singleNumber(int[] nums) {
        int odd = 0;
        for (int num : nums) {
            odd ^= num;
        }
        return odd;
    }
}

note

• time O(n) space O(1)
• The idea is use bitwise manipulation. eg, ((2^2)^(3^3)^(6^6)^5) == (0^0^0^5) == 5