Infinite loops in Go - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of a simple infinite loop with break

What is the output of this Go program?

Go

package main
import "fmt"
func main() {
  i := 0
  for {
    if i == 3 {
      break
    }
    fmt.Print(i)
    i++
  }
}

A 123

B 0123

C 012

D 0

💡 Hint

Look at when the loop stops printing.

The loop prints i starting from 0. When i reaches 3, the break stops the loop before printing 3.

❓ Predict Output

intermediate

Output of infinite loop with continue

What is the output of this Go program?

Go

package main
import "fmt"
func main() {
  i := 0
  for {
    i++
    if i%2 == 0 {
      continue
    }
    if i > 5 {
      break
    }
    fmt.Print(i)
  }
}

A 1357

B 12345

C 246

D 135

💡 Hint

Only odd numbers less than or equal to 5 are printed.

The loop increments i, skips even numbers with continue, prints odd numbers, and stops when i > 5.

🔧 Debug

advanced

Identify the cause of infinite loop

Why does this Go program run forever without stopping?

Go

package main
import "fmt"
func main() {
  i := 0
  for i < 5 {
    fmt.Print(i)
  }
}

A Variable i is never incremented inside the loop

B The loop condition is always false

C The fmt.Print causes the loop to restart

D The for loop syntax is invalid

💡 Hint

Check if the loop variable changes inside the loop.

The variable i stays 0 forever, so the condition i < 5 is always true, causing an infinite loop.

📝 Syntax

advanced

Which option causes a compile error due to infinite loop syntax?

Which of these Go loop statements will cause a compile error?

A for i := 0; i < 5 {}

B for i := 0; i < 5; i++ {}

C for {}

D for i := 0; i < 5; i++ { break }

💡 Hint

Check if the for loop header has all three parts separated by semicolons.

Option A misses the increment part after the second semicolon, causing a syntax error.

🚀 Application

expert

How many times does this infinite loop print?

How many times will the following Go program print "Hello" before stopping?

Go

package main
import "fmt"
func main() {
  count := 0
  for {
    fmt.Println("Hello")
    count++
    if count == 10 {
      break
    }
  }
}

A 9

B 10

C Infinite times

D 0

💡 Hint

Look at how count changes and when the break happens.

The loop prints "Hello" and increments count each time. When count reaches 10, it breaks.