Problem Statement :

Given an array of integers

`nums`

and an integer`target`

, returnindices of the two numbers such that they add up to`.`

targetYou may assume that each input would have

, and you may not use theexactlyone solutionsameelement twice.You can return the answer in any order.

**The brute force way :**

Pick an element and then loop over the entire list to find if target minus element exists. This will be O(N²) time and we can do better.

**Single Pass :**

We can combined looking for the pair of indices into a…

Convert a non-negative integer

`num`

to its English words representation.

**Example 1:**

**Input:** num = 123

**Output:** "One *Hundred* Twenty Three"

**Example 2:**

**Input:** num = 12345

**Output:** "Twelve **Thousand** Three *Hundred* Forty Five"

**Example 3:**

**Input:** num = 1234567

**Output:** "One **Million** Two *Hundred* Thirty Four **Thousand** Five *Hundred*** **Sixty Seven"

**Example 4:**

**Input:** num = 1234567891

**Output:** "One **Billion** Two *Hundred* Thirty Four Million Five *Hundred* Sixty Seven **Thousand** Eight *Hundred* Ninety One"

You may have noticed I have highlighted a few keywords in the examples. Try to look for some sort of pattern before you proceed.

I…