tests: add tests of LongestIncreasingSubsequence (#1660)

Author: vil02

Diff for: Dynamic-Programming/LongestIncreasingSubsequence.js

@@ -6,6 +6,9 @@
 // Return the length of the Longest Increasing Subsequence, given array x
 function longestIncreasingSubsequence(x) {
   const length = x.length
+  if (length == 0) {
+    return 0
+  }
   const dp = Array(length).fill(1)
 
   let res = 1

Diff for: Dynamic-Programming/tests/LongestIncreasingSubsequence.test.js

@@ -0,0 +1,24 @@
+import { longestIncreasingSubsequence } from '../LongestIncreasingSubsequence'
+
+describe('Testing longestIncreasingSubsequence', () => {
+  it.each([
+    [[], 0],
+    [[1], 1],
+    [[2, 2], 1],
+    [[3, 3, 3], 1],
+    [[4, 4, 4, 4], 1],
+    [[1, 2], 2],
+    [[1, 2, 2, 2, 2], 2],
+    [[1, 0, 2], 2],
+    [[1, 10, 2, 30], 3],
+    [[5, 8, 3, 7, 9, 1], 3],
+    [[10, 9, 2, 5, 3, 7, 101, 18], 4],
+    [[10, 10, 9, 9, 2, 2, 5, 5, 3, 3, 7, 7, 101, 101, 18, 18], 4],
+    [[0, 1, 0, 3, 2, 3], 4],
+    [[1, 1, 2, 2, 2], 2],
+    [[1, 1, 2, 2, 2, 3, 3, 3, 3], 3],
+    [[0, 8, 4, 12, 2, 10, 6, 14, 1, 9, 5, 13, 3, 11, 7, 15], 6]
+  ])('check with %j', (input, expected) => {
+    expect(longestIncreasingSubsequence(input)).toBe(expected)
+  })
+})