feat: Added implementation for ugly numbers

DIRECTORY.md

@@ -58,11 +58,17 @@
 ## Graph
   * [Bellman Ford](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/graph/bellman_ford.ts)
   * [Dijkstra](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/graph/dijkstra.ts)
+  * [Floyd Warshall](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/graph/floyd_warshall.ts)
+  * [Johnson](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/graph/johnson.ts)
   * [Kruskal](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/graph/kruskal.ts)
+  * [Prim](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/graph/prim.ts)
   * Test
     * [Bellman Ford.Test](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/graph/test/bellman_ford.test.ts)
     * [Dijkstra.Test](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/graph/test/dijkstra.test.ts)
+    * [Floyd Warshall.Test](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/graph/test/floyd_warshall.test.ts)
+    * [Johnson.Test](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/graph/test/johnson.test.ts)
     * [Kruskal.Test](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/graph/test/kruskal.test.ts)
+    * [Prim.Test](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/graph/test/prim.test.ts)
 
 ## Maths
   * [Absolute Value](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/maths/absolute_value.ts)
@@ -101,6 +107,7 @@
       * [Hexagonal Numbers.Test](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/maths/series/test/hexagonal_numbers.test.ts)
   * [Sieve Of Eratosthenes](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/maths/sieve_of_eratosthenes.ts)
   * [Signum](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/maths/signum.ts)
+  * [Ugly Numbers](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/maths/ugly_numbers.ts)
   * [Zellers Congruence](https://github.com/TheAlgorithms/TypeScript/blob/HEAD/maths/zellers_congruence.ts)
 
 ## Other

maths/test/ugly_numbers.test.ts

@@ -0,0 +1,5 @@
+import { UglyNumbers } from '../ugly_numbers';
+
+test.each([[1, 1], [7, 8], [11, 15]])('Ugly Numbers', (number: number, result: number) => {
+  expect(UglyNumbers(number)).toBe(result)
+})

maths/ugly_numbers.ts

@@ -0,0 +1,39 @@
+/**
+ * @function UglyNumbers
+ * @description Returns the nth ugly number
+ * @summary Ugly numbers are natural numbers whose only prime factors are 2, 3 and 5.
+ * They can be represented in the form 2^a * 3^b * 5*c. By convention, 1 is also considered to be
+ * an ugly number.
+ * The first few terms of the sequence are: 1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 16, 18, 20...
+ * 
+ * For the provided n, the nth ugly number shall be computed.
+ * @param n The nth ugly number to find
+ * @returns {number} The nth ugly number
+ * @see [GeeksForGeeks](https://www.geeksforgeeks.org/ugly-numbers/)
+ * @example UglyNumbers(1) = 1
+ * @example UglyNumbers(7) = 8
+ */
+const UglyNumbers = (n: number) => {
+  const uglyNums = [1];
+  let idx2 = 0;
+  let idx3 = 0;
+  let idx5 = 0;
+  let nextx2: number, nextx3: number, nextx5: number, nextNum: number;
+
+  while (uglyNums.length < n) {
+    nextx2 = uglyNums[idx2] * 2;
+    nextx3 = uglyNums[idx3] * 3;
+    nextx5 = uglyNums[idx5] * 5;
+    nextNum = Math.min(nextx2, nextx3, nextx5);
+
+    uglyNums.push(nextNum);
+
+    if (nextx2 === nextNum) idx2++;
+    if (nextx3 === nextNum) idx3++;
+    if (nextx5 === nextNum) idx5++;
+  }
+
+  return uglyNums[n - 1];
+}
+
+export { UglyNumbers }