Step 2: Counting the Words Using a HashMap

Why a HashMap?

A HashMap provides an efficient way to store key-value pairs. In our case, the word will be the key, and its frequency will be the value. This will enable us to look up the frequency of a word in constant time.

How to Count?

We'll initialize an empty HashMap (or an object in JavaScript, or a dictionary in Python) to store the occurrences of each word. Let's call this HashMap occurrences.

Counting the Words Using a HashMap

Code Snippet for Counting

Here's how you can populate the occurrences HashMap:

1Dictionary<string, int> occurrences = new Dictionary<string, int>();
2foreach(var word in split_s) {
3    if (occurrences.ContainsKey(word)) {
4        occurrences[word]++;
5    } else {
6        occurrences[word] = 1;
7    }
8}