Golang Interview Questions

Need to practice your Go programming skills for an upcoming job interview? Try solving these Go interview questions that test knowledge of Go programming concepts such as slices, interfaces, built-in functions, and other skills. We’ll provide feedback on your answers, and you can use a hint if you get stuck.

These Go interview questions are examples of real tasks used by employers to screen job candidates such as Go developers, back-end developers, and others that need to solve problems using the Go programming language and it’s rich set of built-in functions.

1. Merge Names

Slices

Easy

Implement the uniqueNames function. When passed two slices of names, it will return a slice containing the names that appear in either or both slices. The returned slice should have no duplicates.

For example, calling uniqueNames([]string{"Ava", "Emma", "Olivia"}, []string{"Olivia", "Sophia", "Emma"}) should return a slice containing Ava, Emma, Olivia, and Sophia in any order.

Go 1.13

Show starting code

package main
import "fmt"

func uniqueNames(a, b []string) []string {
    var result []string
    return result
}
    
func main() {
    // should print Ava, Emma, Olivia, Sophia
    fmt.Println(uniqueNames(
        []string{"Ava", "Emma", "Olivia"}, 
        []string{"Olivia", "Sophia", "Emma"}))  
}

Report an issue

Example case: Wrong answer
Each slice has distinct names: Wrong answer
Each slice has duplicate names: Wrong answer
Slices have some names in common: Wrong answer

2. Quadratic Equation

Arithmetic

Easy

Implement the function findRoots to find the roots of the quadratic equation: ax² + bx + c = 0. If the equation has only one solution, the function should return that solution as both results. The equation will always have at least one solution.

The roots of the quadratic equation can be found with the following formula:

For example, the roots of the equation 2x² + 10x + 8 = 0 are -1 and -4.

Go 1.13

Show starting code

package main
import "fmt"

func findRoots(a, b, c float64) (float64, float64) {
    return 0, 0
}
    
func main() {
    x1, x2 := findRoots(2, 10, 8)
    fmt.Printf("Roots: %f, %f", x1, x2)
}

Report an issue

Example case: Wrong answer
Equal roots: Wrong answer
Distinct roots: Wrong answer

3. Numeric Input

Interfaces

Easy

User interface contains NumericInput control, which accepts only digits.

Extend NumericInput structure so that:

It implements UserInput interface.
Add(rune) should add only decimal digits to the input. Other runes should be ignored.
GetValue() should return the current input.

For example, the following code should output "10":

var input UserInput = &NumericInput{}
input.Add('1')
input.Add('a')
input.Add('0')
fmt.Println(input.GetValue())

Go 1.13

Show starting code

package main
//import "fmt"

type UserInput interface {
   Add(rune)
   GetValue() string
}

type NumericInput struct {
   input string
}
  
func main() {
    //var input UserInput = &NumericInput{}
    //input.Add('1')
    //input.Add('a')
    //input.Add('0')
    //fmt.Println(input.GetValue())
}

Report an issue

Example case: Wrong answer
GetValue() returns input: Wrong answer
Add(rune) adds runes to the input: Wrong answer
Add(rune) adds only decimal digits to the input: Wrong answer

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Golang Interview Questions

Practice for Go interviews by solving TestDome questions. Our interview questions are used by more than 7,000 companies and 450,000 individual test takers.

1. Merge Names

2. Quadratic Equation

3. Numeric Input