Merge pull request #30 from msach22/duplicates

Duplicates #16

solutions/16.js

@@ -0,0 +1,17 @@
+//msach22
+// should return true if the input array has duplicate values and false if it doesn't
+
+const hasDuplicates = (array) => {
+  let map = {};
+  for (let i = 0; i < array.length; i++) {
+    if (map[array[i]]) {
+      return true;
+    }
+    map[array[i]] = true;
+  };
+  return false;
+}
+
+module.exports = {
+  hasDuplicates
+};

test/16.js

@@ -0,0 +1,18 @@
+const expect = require('chai').expect;
+const duplicates = require('../solutions/16');
+const hasDuplicates = duplicates.hasDuplicates;
+
+describe('check duplicates', () => {
+  it('should return true since array has duplicates', () => {
+    const array = [1,2,3,3,4];
+    expect(hasDuplicates(array)).to.be.true;
+  });
+  it('should return false because array does not have duplicates', () => {
+    const array = [1,2,3,4];
+    expect(hasDuplicates(array)).to.be.false;
+  });
+  it('should return false because array is empty', () => {
+    const array = [];
+    expect(hasDuplicates(array)).to.be.false;
+  });
+});