Count the Number of Each Vowel in Go

In this tutorial, we will learn how to count the number of each vowel in a string in Go. We will cover the basic concept of string manipulation and implement a function to perform the counting.

What is String Manipulation

String manipulation involves altering, parsing, and analyzing strings in various ways. Counting the number of each vowel in a string is a common task in text processing.

Syntax

The syntax to count the number of each vowel in a string in Go is:

import (
    "fmt"
    "strings"
)

func countVowels(s string) map[rune]int {
    vowels := "aeiouAEIOU"
    vowelCount := make(map[rune]int)
    for _, char := range s {
        if strings.ContainsRune(vowels, char) {
            vowelCount[char]++
        }
    }
    return vowelCount
}

Example 1: Counting the number of each vowel in a string

We can create a function to count the number of each vowel in a given string by iterating through its characters and checking if they are vowels.

For example,

  1. Import the fmt and strings packages.
  2. Define a function named countVowels that takes one parameter s of type string.
  3. Initialize a string vowels containing all vowel characters.
  4. Initialize a map vowelCount to store the count of each vowel.
  5. Use a for loop to iterate through the characters of the input string.
  6. In each iteration, check if the character is a vowel using strings.ContainsRune. If true, increment the count in the map.
  7. Return the map of vowel counts.
  8. In the main function, call the countVowels function with a sample string and print the result.

Go Program

package main

import (
    "fmt"
    "strings"
)

func countVowels(s string) map[rune]int {
    vowels := "aeiouAEIOU"
    vowelCount := make(map[rune]int)
    for _, char := range s {
        if strings.ContainsRune(vowels, char) {
            vowelCount[char]++
        }
    }
    return vowelCount
}

func main() {
    // Sample string
    sampleString := "Hello, world! Welcome to Go programming."

    // Count the number of each vowel in the sample string
    result := countVowels(sampleString)

    // Print the result
    fmt.Println("Vowel counts:", result)
}

Output

Vowel counts: map[A:0 E:2 I:0 O:4 U:0 a:0 e:2 i:0 o:4 u:0]