Basic data types in Go - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the output of this Go code snippet?

Consider the following Go program. What will it print when run?

Go

package main
import "fmt"
func main() {
    var a int = 5
    var b float64 = 3.2
    var c bool = true
    fmt.Println(a, b, c)
}

A 5 3.2 true

B 5 3 true

C 5 3.2 1

D 5 3.2 false

💡 Hint

Remember that fmt.Println prints values separated by spaces and booleans print as true or false.

The variables a, b, and c are printed as their values: integer 5, float 3.2, and boolean true.

❓ Predict Output

intermediate

What is the output of this Go code with type conversion?

What does this Go program print?

Go

package main
import "fmt"
func main() {
    var x int = 10
    var y float64 = float64(x) / 4
    fmt.Printf("%.2f", y)
}

A 2.00

B 2.5

C 2.50

D 2

💡 Hint

Look at the Printf format specifier and the type conversion.

The integer 10 is converted to float64, then divided by 4, resulting in 2.5. The format %.2f prints two decimal places, so output is 2.50.

🔧 Debug

advanced

What error does this Go code produce?

What error will this Go program cause when compiled?

Go

package main
func main() {
    var a int = "hello"
    println(a)
}

A undefined: a

B cannot use "hello" (type string) as type int in assignment

C missing return statement

D syntax error: unexpected string literal

💡 Hint

Check the variable type and the assigned value type.

The variable a is declared as int but assigned a string. This causes a type mismatch error.

🧠 Conceptual

advanced

How many bytes does a Go int use on a 64-bit system?

On a 64-bit system, how many bytes does the int type occupy in Go?

A 16 bytes

B Depends on the compiler

C 4 bytes

D 8 bytes

💡 Hint

Think about the system architecture and Go's default int size.

On 64-bit systems, Go's int type is 64 bits, which equals 8 bytes.

🚀 Application

expert

What is the value of variable 'result' after running this Go code?

Given the code below, what is the value of result after execution?

Go

package main
func main() {
    var a uint8 = 250
    var b uint8 = 10
    var result uint8 = a + b
    println(result)
}

A 4

B overflow error

C 260

D 250

💡 Hint

Remember that uint8 can only hold values from 0 to 255 and wraps around on overflow.

Adding 250 + 10 equals 260, but uint8 max is 255, so it wraps around: 260 - 256 = 4.