Longest increasing sequence.

Author: simdi

fib/test.js

@@ -8,19 +8,19 @@ describe('Fibonacci Tests', () => {
   test('Fib function is defined', () => {
     expect(typeof fib).toEqual('function');
   });
-  it('Calculate correct fib value for 1 === 1', async() => {
+  it('Calculate correct fib value for 1 === 1', () => {
     expect(fib(1)).toEqual(1);
   });
-  it('Calculate correct fib value for 2 === 1', async() => {
+  it('Calculate correct fib value for 2 === 1', () => {
     expect(fib(2)).toEqual(1);
   });
-  it('Calculate correct fib value for 5 === 5', async() => {
+  it('Calculate correct fib value for 5 === 5', () => {
     expect(fib(5)).toEqual(5);
   });
-  test('Calculate correct fib value for 6 === 8', async() => {
+  test('Calculate correct fib value for 6 === 8', () => {
     expect(fib(6)).toEqual(8);
   });
-  test('Calculate correct fib value for 50 === 12586269025', async() => {
+  test('Calculate correct fib value for 50 === 12586269025', () => {
     expect(fib(50)).toEqual(12586269025);
   });
 });

lis/index.js

@@ -0,0 +1,24 @@
+/*
+* @author: Chisimdi Damian Ezeanieto
+* @date: 23/06/2020
+*/
+// Find the longest increasing subsequence in a given array.
+// Longest Increasing Subsequence
+const lis = (arr) => {
+  if (arr.length < 1) return undefined;
+  // Fill an array of length arr.length with 1;
+  const lis = Array(arr.length).fill(1);
+
+  let n = arr.length;
+  for(let i = 1; i <= n; i++) {
+    for(let j = 0; j < i; j++) {
+      if (arr[j] < arr[i]) {
+        lis[i] = Math.max(lis[j] + 1, lis[i]);
+      }
+    }
+  }
+
+  return Math.max(...lis);
+};
+
+module.exports = lis;

lis/test.js

@@ -0,0 +1,14 @@
+/*
+* @author: Chisimdi Damian Ezeanieto
+* @date: 23/06/2020
+*/
+const lis = require('./index');
+
+describe('Longest Increasing Subsequence Tests', () => {
+  test('lis function is defined', () => {
+    expect(typeof lis).toEqual('function');
+  });
+  it('Calculate correct lis value for [5,7,4,-3,9,1,10,4,5,8,9,3] === 6', () => {
+    expect(lis([5,7,4,-3,9,1,10,4,5,8,9,3])).toEqual(6);
+  });
+});