What is Go - Interactive Quiz & Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to print a greeting in Go.

Go

package main

import "fmt"

func main() {
    fmt.[1]("Hello, Go!")
}

Drag options to blanks, or click blank then click option'

APrintln

BPrint

CPrintf

DPrintfln

Attempts:

3 left

💡 Hint

Common Mistakes

Using Print instead of Println will not add a new line.

The Println function prints the text with a new line at the end.

2fill in blank

medium

Complete the code to declare a variable with value 10.

Go

package main

func main() {
    var x [1] = 10
}

Drag options to blanks, or click blank then click option'

Abool

Bint

Cfloat

Dstring

Attempts:

3 left

💡 Hint

Common Mistakes

Using string or bool types for numbers.

The int type is used for whole numbers like 10.

3fill in blank

hard

Fix the error in the function declaration.

Go

package main

func [1]() {
    // code
}

Drag options to blanks, or click blank then click option'

Adef

Bfunction

Cfunc

Dmain

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'function' or 'def' which are not Go keywords.

The function name must be main exactly for the program entry point.

4fill in blank

hard

Fill both blanks to create a map with string keys and int values.

Go

package main

func main() {
    m := make(map[[1]][2])
}

Drag options to blanks, or click blank then click option'

Astring

Bint

Cfloat64

Dbool

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up key and value types.

Maps use key and value types inside brackets. Here keys are strings and values are integers.

5fill in blank

hard

Fill all three blanks to declare a slice of strings and add an element.

Go

package main

import "fmt"

func main() {
    var s [][1]
    s = append(s, [2])
    fmt.[3](s)
}

Drag options to blanks, or click blank then click option'

Aint

B"hello"

CPrintln

Dstring

Attempts:

3 left

💡 Hint

Common Mistakes

Using int instead of string for the slice type.

A slice of strings is declared with []string. We append a string literal and print with Println.

Practice

1. What is Go primarily used for?

easy

A. Designing websites with HTML

B. Building fast and reliable software

C. Creating video games only

D. Writing scripts for Photoshop

Solution

1. Step 1: Understand Go's purpose

   Go is designed to build software that runs quickly and reliably.

2. Step 2: Compare options

   Options A, C, and D describe other technologies or limited uses, not Go's main purpose.

3. Final Answer:

   Building fast and reliable software -> Option B

4. Quick Check:

   Go = fast, reliable software [OK]

Hint: Go is known for speed and reliability [OK]

Common Mistakes:

• Confusing Go with web design languages
• Thinking Go is only for games
• Assuming Go is a scripting tool

2. Which of the following is the correct way to start a Go program?

easy

A. package main

func main() {
// code
}

B. start program {
// code
}

C. begin main() {
// code
}

D. function main() {
// code
}

Solution

1. Step 1: Recognize Go program structure

   Go programs start with a package declaration and a main function.

2. Step 2: Check syntax correctness

   package main func main() { // code } uses correct Go syntax: 'package main' and 'func main()'. Others use invalid keywords or syntax.

3. Final Answer:

   package main\n\nfunc main() {\n // code\n} -> Option A

4. Quick Check:

   Go starts with package main and func main() [OK]

Hint: Go programs start with 'package main' and 'func main()' [OK]

Common Mistakes:

• Using 'start' or 'begin' instead of 'package' and 'func'
• Omitting the package declaration
• Using wrong function syntax

3. What will be the output of this Go program?

package main
import "fmt"
func main() {
    fmt.Println("Hello, Go!")
}

medium

A. Hello Go

B. fmt.Println("Hello, Go!")

C. Hello, Go!

D. Error: missing main function

Solution

1. Step 1: Understand fmt.Println usage

   fmt.Println prints the string with a newline to the console.

2. Step 2: Check the program structure

   The program has a valid main function and imports fmt correctly, so it runs and prints the string.

3. Final Answer:

   Hello, Go! -> Option C

4. Quick Check:

   fmt.Println prints text with newline [OK]

Hint: fmt.Println prints exactly what is inside quotes [OK]

Common Mistakes:

• Expecting output without quotes
• Confusing print with return
• Thinking program lacks main function

4. Identify the error in this Go code:

package main
import "fmt"
func main() {
    fmt.Println("Welcome to Go")
    fmt.Println(Welcome to Go)
}

medium

A. Missing quotes around string in second fmt.Println

B. Missing import statement

C. No main function defined

D. Incorrect package name

Solution

1. Step 1: Check string usage in fmt.Println

   The second fmt.Println lacks quotes around the string, causing a syntax error.

2. Step 2: Verify other parts

   Import and main function are correct, package name is valid.

3. Final Answer:

   Missing quotes around string in second fmt.Println -> Option A

4. Quick Check:

   Strings need quotes in fmt.Println [OK]

Hint: Strings must be in quotes inside fmt.Println [OK]

Common Mistakes:

• Forgetting quotes around strings
• Assuming import is missing
• Thinking main function is absent

5. You want to write a Go program that prints "Go is fun!" only if a variable fun is true. Which code snippet correctly does this?

hard

A. package main
import "fmt"
func main() {
fun := true
fmt.Println("Go is fun!")
}

B. package main
import "fmt"
func main() {
fun := true
if fun == false {
fmt.Println("Go is fun!")
}
}

C. package main
import "fmt"
func main() {
fun := false
if fun {
fmt.Println("Go is fun!")
}
}

D. package main
import "fmt"
func main() {
fun := true
if fun {
fmt.Println("Go is fun!")
}
}

Solution

1. Step 1: Understand the condition to print

   The program should print only if 'fun' is true, so the if condition must check 'fun' directly.

2. Step 2: Analyze each option

   package main import "fmt" func main() { fun := true if fun { fmt.Println("Go is fun!") } } checks 'if fun' when fun is true, so it prints. package main import "fmt" func main() { fun := true if fun == false { fmt.Println("Go is fun!") } } prints if fun is false, wrong. package main import "fmt" func main() { fun := false if fun { fmt.Println("Go is fun!") } } fun is false, so no print. package main import "fmt" func main() { fun := true fmt.Println("Go is fun!") } prints unconditionally, ignoring fun.

3. Final Answer:

   package main\nimport \"fmt\"\nfunc main() {\n fun := true\n if fun {\n fmt.Println(\"Go is fun!\")\n }\n} -> Option D

4. Quick Check:

   Print only if fun is true [OK]

Hint: Use 'if fun' to check true boolean variable [OK]

Common Mistakes:

• Checking if fun == false instead of fun
• Setting fun to false by mistake
• Printing without condition