Word Counter: Basic Algorithm

Now it's time to implement your own simple word counter! Let's create a function that counts the number of words in text by analyzing a slice of bytes.

The Problem

Given text stored as a slice of bytes (like when reading from a file), how do we count the words?

For example, this text has 5 words:

"Hello world from the matrix"

Your challenge is to figure out how to count them!

Working with Bytes

When you read text from a file, it comes as a slice of bytes ([]byte). Each character is represented as a byte:

text := []byte("Hello world")
fmt.Println(text)
// Output: [72 101 108 108 111 32 119 111 114 108 100]

Each number represents a character. For example, 72 is 'H', 101 is 'e', and so on.

Iterating Over Bytes

Use range to iterate over each byte in the slice:

data := []byte("Hello world")

for _, b := range data {
    fmt.Println(b)
}
// Output: prints each byte value (72, 101, 108, 108, 111, 32, ...)

The first value from range is the index (which we ignore with _), and the second is the actual byte value.

Comparing Bytes to Characters

You can compare a byte directly to a character using single quotes:

data := []byte("Hello world")

for _, b := range data {
    if b == ' ' {
        fmt.Println("Found a space!")
    }
    if b == 'H' {
        fmt.Println("Found an H!")
    }
}

Important: Use single quotes ' ' for characters, not double quotes " " (which are for strings).

Think About the Strategy

Before you start coding, think about:

• What separates words in text?
• How can you use that to count words?
• Look at the example: "Hello world from the matrix" - what pattern do you notice?

Hints for Your Algorithm

• You'll need a variable to keep track of your count
• You'll need to loop through all the bytes
• Think about what character appears between words
• Consider: if you have 4 spaces, how many words do you have?

Assignment

Implement the countWords function that accepts a slice of bytes and returns the number of words.

The function signature is:

func countWords(data []byte) int {
    // Your code here
}

Test cases:

• []byte("Goku Vegeta Gohan") should return 3
• []byte("Hello world") should return 2
• []byte("Hi") should return 1