Learn How to reverse a string in Golang

In this article, you will learn about how to reverse a string in the Go language.

Reverse a string means printing a given string from the backward. Like, the first letter of a given string to the last and last one into the first and so on. You can perform this action in Go language easily.

Let’s imagine you have a given string that is “morning” and now you want to reverse it as “gninrom”. You can simply do it in Go language. See the code example below:

package main

import "fmt"

func reverse(s string) string {
        rns := []rune(s)
        for i, j := 0, len(rns)-1; i < j; i, j = i+1, j-1 {
                rns[i], rns[j] = rns[j], rns[i]
        }
        return string(rns)
}

func main() {

        str := "morning"
        strRev := reverse(str)
        fmt.Println(str)
        fmt.Println(strRev)
}

// Output : 
// morning
// gninrom

You can also perform the same action by declaring an empty string and appending them from last to first. Let’s see the below code example to make things more clear to you:

 package main
    
    import "fmt"
    
    func reverse(str string) (result string) {
            for _, v := range str {
                    result = string(v) + result
            }
            return
    }
    
    func main() {
    
            str := "morning"
            strRev := reverse(str)
            fmt.Println(str)
            fmt.Println(strRev)
    }
    
    // Output:
    // morning
    // gninrom

Like reversing a single word, you can also reverse multiple words. For example, you have an array of three fruits "apple, banana, orange" and you want to reverse them as " orange, banana, apple". It is also possible in Go language. To do so, we have to convert these strings into an array of strings and then simply apply the reverse loop. See the code example below:

    package main
    
    import (
            "fmt"
            "strings"
    )
    
    func reverse_words(s string) string {
            words := strings.Fields(s)
            for i, j := 0, len(words)-1; i < j; i, j = i+1, j-1 {
                    words[i], words[j] = words[j], words[i]
            }
            return strings.Join(words, " ")
    }
    
    func main() {
            fmt.Println("apple banana orange")
            fmt.Println(reverse_words("apple banana orange"))
    }
    
    // Output:
    // apple banana orange
    // orange banana apple

This is all about reversing a string in the Go language.