Added Single Number

Author: gahogg

Single Number - Leetcode 136/Single Number - Leetcode 136.cpp

@@ -0,0 +1,10 @@
+class Solution {
+public:
+    int singleNumber(vector<int>& nums) {
+        int a = 0;
+        for (int x : nums) {
+            a ^= x;
+        }
+        return a;
+    }
+};

Single Number - Leetcode 136/Single Number - Leetcode 136.java

@@ -0,0 +1,9 @@
+public class Solution {
+    public int singleNumber(int[] nums) {
+        int a = 0;
+        for (int x : nums) {
+            a ^= x;
+        }
+        return a;
+    }
+}

Single Number - Leetcode 136/Single Number - Leetcode 136.js

@@ -0,0 +1,7 @@
+var singleNumber = function(nums) {
+    let a = 0;
+    for (let x of nums) {
+        a ^= x;
+    }
+    return a;
+};

Single Number - Leetcode 136/Single Number - Leetcode 136.py

@@ -0,0 +1,10 @@
+class Solution(object):
+    def singleNumber(self, nums: List[int]) -> int:
+        a = 0
+
+        for x in nums:
+            a ^= x
+
+        return a
+        # Time: O(n)
+        # Space: O(1)