.github/workflows/node.js.yml

@@ -0,0 +1,31 @@
+# This workflow will do a clean installation of node dependencies, cache/restore them, build the source code and run tests across different versions of node
+# For more information see: https://docs.github.com/en/actions/automating-builds-and-tests/building-and-testing-nodejs
+
+name: Node.js CI
+
+on:
+  push:
+    branches: [ "master" ]
+  pull_request:
+    branches: [ "master" ]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        node-version: [14.x, 16.x, 18.x]
+        # See supported Node.js release schedule at https://nodejs.org/en/about/releases/
+
+    steps:
+    - uses: actions/checkout@v3
+    - name: Use Node.js ${{ matrix.node-version }}
+      uses: actions/setup-node@v3
+      with:
+        node-version: ${{ matrix.node-version }}
+        cache: 'npm'
+    - run: npm ci
+    - run: npm run build --if-present
+    - run: npm test

README.md

@@ -2,7 +2,6 @@
 
 # Problem Solving using Javascript
 
-[![Open Source Love](https://badges.frapsoft.com/os/v2/open-source.svg?v=103)](https://github.com/vinitshahdeo/HacktoberFest)
 [![Build Status](https://travis-ci.org/knaxus/problem-solving-javascript.svg?branch=master)](https://travis-ci.org/knaxus/problem-solving-javascript)
 [![Coverage Status](https://coveralls.io/repos/github/knaxus/problem-solving-javascript/badge.svg?branch=master)](https://coveralls.io/github/knaxus/problem-solving-javascript?branch=master)
 ![GitHub stars](https://img.shields.io/github/stars/knaxus/problem-solving-javascript)
@@ -41,6 +40,6 @@ Find the detailed contents and problem list here: [Table Of Contents](TOC.md)
 
 ## Contribution Guide
 
-It's great to know that you want to contribute to this repo. Thanks for taking interest. please find the [guide here](https://github.com/knaxus/problem-solving-javascript/blob/master/CONTRIBUTING.md)
+It's great to know that you want to contribute to this repo. Thanks for taking interest. Please find the [guide here](https://github.com/knaxus/problem-solving-javascript/blob/master/CONTRIBUTING.md)
 
-Keep an eye on this guide, it's subjected to change frequently.
+Keep an eye on this guide. It's subject to frequent change.

TOC.md

@@ -76,7 +76,7 @@
 - [Next Greater for Every Element in an Array](src/_Problems_/next-greater-element)
 - [Compose Largest Number](src/_Problems_/compose-largest-number)
 - [Rotate Image](src/_Problems_/rotate-image)
-
+- [3 Sum](src/_Problems_/3Sum/)
 ### Searching
 
 - [Binary Search](src/_Searching_/BinarySearch)

src/_DataStructures_/Set/setTest.js

@@ -0,0 +1,43 @@
+const letters = require('./index');
+
+describe('Data Structure : Set', () => {
+
+
+  it('X Set should be a Class', () => {
+    expect(typeof XSet.prototype.constructor).toEqual('function');
+  });
+
+  describe('Creation of Set', () => {
+
+    it('Should create a new Set with no elements', () => {
+      letters = new XSet();
+      expect(letters === 0);
+    });
+
+    it('Should add letter A', () => {
+      letters.add('a');
+      expect(letters.has('a');
+    });
+
+    it('Should add letter B', () => {
+      letters.add('b');
+      expect(letters.has('b');
+    });
+
+    it('Should add letter C', () => {
+      letters.add('c');
+      expect(letters.has('c');
+    });
+
+    it('Should remove letter A', () => {
+      letters.remove('a');
+      expect(!letters.has('a');
+    });
+
+    it('Should remove letter B', () => {
+      letters.remove('b');
+      expect(!letters.has('b');
+    });
+
+
+  });

src/_Problems_/3Sum/3sum.js

@@ -0,0 +1,39 @@
+const threeSum = function(nums) {
+    // sort the array
+    nums = nums.sort((a, b) => a - b);
+
+    let result = [];
+    // iterate through the array and use two pointers to find the sum
+    for (let i = 0; i < nums.length; ++i) {
+        let left = i + 1;
+        let right = nums.length - 1;
+        while (left < right) {
+            let sum = nums[i] + nums[left] + nums[right];
+            if (sum == 0) {
+                result.push([nums[i], nums[left], nums[right]]);
+                left++;
+                right--;
+            }
+            else if (sum < 0) {
+                left++;
+            }
+            else {
+                right--;
+            }
+        }
+        // skip duplicates
+        while (i < nums.length - 1 && nums[i] == nums[i + 1]) {
+            i++;
+        }
+    }
+
+    // initialize set to remove duplicate 
+    const set = new Set(result.map(JSON.stringify));
+    // final output array
+    output = (new Array(...set).map(JSON.parse));
+    return output;
+};
+
+
+module.exports = threeSum;
+

src/_Problems_/3Sum/3sum.test.js

@@ -0,0 +1,19 @@
+const threeSum = require("./3sum");
+
+describe("threeSum", () => {
+    it("Should return [[-1, -1, 2], [-1, 0, 1]]", () => {
+        expect(threeSum([-1, 0, 1, 2, -1, -4])).toEqual([
+            [-1, -1, 2],
+            [-1, 0, 1],
+        ]);
+    });
+
+    it("Should return [[0, 0, 0]]", () => {
+        expect(threeSum([0, 0, 0])).toEqual([[0, 0, 0]]);
+    });
+
+    it("Should return [[-1, -1, 2]]", () => {
+        expect(threeSum([-1, 2, -1, -4])).toEqual([[-1, -1, 2]]);
+    });
+
+});