Single number js (#225)

* Single Number JavaScript

* single number JavaScript added tests

Author: dragonstin

JavaScript/single-number.js

@@ -0,0 +1,52 @@
+/**
+ * Given a non-empty array of integers, every element appears twice except for
+ * one. Find that single one.
+ * 
+ * Note:
+ * 
+ * Your algorithm should have a linear runtime complexity. Could you implement
+ * it without using extra memory?
+ * 
+ * Example 1:
+ * 
+ * Input: [2,2,1] Output: 1
+ * 
+ * Example 2:
+ * 
+ * Input: [4,1,2,1,2] Output: 4
+ *
+ */
+
+/**
+ * @param {number[]} nums
+ * @return {number}
+ */
+var singleNumber = function(nums) {
+    result= []
+    nums.sort()
+    
+    nums.forEach(element => {
+        if (result.indexOf(element) == -1){
+            result.push(element)
+        }else{
+            result.splice(result.indexOf(element),1)
+        }
+    });
+
+    return result[0]
+};
+
+
+
+//------- Test cases -----------------
+// Input: nums = [2,2,1]
+// Output: 1
+console.log(`Example 01 = ${singleNumber([2,2,1])} expected Output 1.`)
+
+// Input: nums = [4,1,2,1,2]
+// Output: 4
+console.log(`Example 02 = ${singleNumber([4,1,2,1,2])} expected Output 4.`)
+
+// Input: nums = [1]
+// Output: 1
+console.log(`Example 03 = ${singleNumber([1])} expected Output 1.`)

README.md

@@ -84,7 +84,7 @@ Check out ---> [Sample PR](https://github.com/codedecks-in/LeetCode-Solutions/pu
 
 | #    | Title                                                                                 | Solution                                                                                                       | Time   | Space  | Difficulty | Tag | Tutorial                                 |
 | ---- | ------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------- | ------ | ------ | ---------- | --- | ---------------------------------------- |
-| 136  | [Single Number](https://leetcode.com/problems/single-number/)                         | [Java](./Java/single-number.java) <br> [Python](./Python/single-number.py) <br> [C++](./C++/Single-Number.cpp) | _O(n)_ | _O(1)_ | Easy       |     | Using XOR                                |
+| 136  | [Single Number](https://leetcode.com/problems/single-number/)                         | [Java](./Java/single-number.java) <br> [Python](./Python/single-number.py) <br> [C++](./C++/Single-Number.cpp) <br> [JavaScript](./JavaScript/single-number.js) | _O(n)_ | _O(1)_ | Easy       |     | Using XOR                                |
 | 137  | [Single Number II](https://leetcode.com/problems/single-number-ii/)                   | [Python](./Python/single-number-ii.py)<br/> [C++](./C++/Single-Number-II.cpp)                                  | _O(n)_ | _O(1)_ | Medium     |     |                                          |
 | 260  | [Single Number III](https://leetcode.com/problems/single-number-iii/)                 | [Python](./Python/single-number-iii.py) <br/> [C++](./C++/Single-Number-III.cpp) | _O(n)_ | _O(1)_ | Medium     |     |                                          |
 | 371 | [Sum of Two Integers](https://leetcode.com/problems/sum-of-two-integers/) | [Java](./Java/Sum_of_two_integers.java) | _O(1)_ | _O(1)_ | Medium     |