Break statement in Go - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of break in nested loops

What is the output of this Go program?

Go

package main
import "fmt"
func main() {
    for i := 1; i <= 3; i++ {
        for j := 1; j <= 3; j++ {
            if j == 2 {
                break
            }
            fmt.Printf("%d%d ", i, j)
        }
    }
}

A 11 12 21 22 31 32

B 11 21 31

C 11 12 21 31

D 11 21 22 31

💡 Hint

Remember, break exits the innermost loop only.

The break statement stops the inner loop when j == 2, so only j=1 prints for each i. Output is 11 21 31.

❓ Predict Output

intermediate

Break with label in Go

What is the output of this Go program using a labeled break?

Go

package main
import "fmt"
func main() {
Outer:
    for i := 1; i <= 3; i++ {
        for j := 1; j <= 3; j++ {
            if i*j >= 4 {
                break Outer
            }
            fmt.Printf("%d%d ", i, j)
        }
    }
}

A 11 12 13 21 22 23 31 32 33

B 11 12 13 21 22 23

C 11 12 21 22

D 11 12 13 21

💡 Hint

A labeled break exits the outer loop entirely.

When i*j >= 4, break Outer exits both loops. The first time this happens is at i=2, j=2 (2*2=4). So output is 11 12 13 21.

🔧 Debug

advanced

Why does this break not stop the loop?

Consider this Go code snippet. Why does the loop not stop when the break statement is reached?

Go

package main
import "fmt"
func main() {
    for i := 0; i < 5; i++ {
        if i == 3 {
            break
        }
        fmt.Println(i)
    }
    fmt.Println("Loop ended")
}

A The break is inside the if but the condition is never true, so break never runs.

B The break only exits the inner block, not the loop.

C The break exits the loop, but the print after the loop runs anyway.

D The break is misplaced and causes a compile error.

💡 Hint

Check what break does and what happens after the loop.

The break stops the loop when i == 3, so the loop ends early. The print after the loop runs normally.

📝 Syntax

advanced

Identify the syntax error with break

Which option contains a syntax error related to the break statement in Go?

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

B for i := 0; i < 5; i++ { if i == 2 { break } }

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

D for i := 0; i < 5; i++ { if i == 3 { break } }

💡 Hint

Check if the label is declared before using break label.

Option A uses break label without declaring label, causing a compile error.

🚀 Application

expert

Count iterations before break with label

How many times does the inner loop print before the program breaks out of both loops?

Go

package main
import "fmt"
func main() {
Outer:
    for i := 1; i <= 4; i++ {
        for j := 1; j <= 4; j++ {
            if i+j > 5 {
                break Outer
            }
            fmt.Printf("%d%d ", i, j)
        }
    }
}

A 9

B 10

C 8

D 7

💡 Hint

Count all pairs (i,j) where i+j <= 5 before break Outer triggers.

Pairs printed are (1,1),(1,2),(1,3),(1,4),(2,1),(2,2),(2,3),(3,1),(3,2). Total 9 prints before break.

Practice

1. What does the break statement do inside a loop in Go?

easy

A. It pauses the loop for a moment and then continues.

B. It skips the current iteration and moves to the next one.

C. It immediately stops the loop and continues after it.

D. It restarts the loop from the beginning.

Solution

1. Step 1: Understand the role of break in loops

   The break statement is used to exit a loop immediately, stopping any further iterations.

2. Step 2: Compare with other loop controls

   Unlike continue which skips to the next iteration, break stops the loop entirely and moves on.

3. Final Answer:

   It immediately stops the loop and continues after it. -> Option C

4. Quick Check:

   Break stops loop = It immediately stops the loop and continues after it. [OK]

Hint: Break stops loop immediately, no more repeats [OK]

Common Mistakes:

• Confusing break with continue
• Thinking break pauses the loop
• Assuming break restarts the loop

2. Which of the following is the correct syntax to use break inside a for loop in Go?

easy

A. for i := 0; i < 5; i++ { if i == 3 { exit } }

B. for i := 0; i < 5; i++ { if i == 3 { stop } }

C. for i := 0; i < 5; i++ { if i == 3 { continue } }

D. for i := 0; i < 5; i++ { if i == 3 { break } }

Solution

1. Step 1: Identify the correct keyword for stopping a loop

   In Go, break is the keyword used to exit a loop early.

2. Step 2: Check syntax correctness

   for i := 0; i < 5; i++ { if i == 3 { break } } uses break correctly inside an if statement within the for loop.

3. Final Answer:

   for i := 0; i < 5; i++ { if i == 3 { break } } -> Option D

4. Quick Check:

   Correct break syntax = for i := 0; i < 5; i++ { if i == 3 { break } } [OK]

Hint: Use 'break' keyword exactly to stop loops [OK]

Common Mistakes:

• Using 'stop' or 'exit' instead of 'break'
• Confusing 'continue' with 'break'
• Missing curly braces around break

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

for i := 1; i <= 5; i++ {
    if i == 3 {
        break
    }
    fmt.Print(i, " ")
}

medium

A. 1 2 3 4 5

B. 1 2

C. 3 4 5

D. 1 2 3

Solution

1. Step 1: Trace the loop iterations

   The loop starts at i=1 and prints i. When i=3, the break stops the loop immediately.

2. Step 2: Determine printed values before break

   Values printed before break are 1 and 2, then loop stops before printing 3.

3. Final Answer:

   1 2 -> Option B

4. Quick Check:

   Break at 3 stops loop = 1 2 [OK]

Hint: Break stops before printing 3, so only 1 and 2 print [OK]

Common Mistakes:

• Including 3 in output
• Printing all numbers ignoring break
• Confusing break with continue

4. Find the error in this Go code snippet using break:

for i := 0; i < 5; i++ {
    if i == 2 {
        break 2
    }
    fmt.Println(i)
}

medium

A. Using break with a number is invalid in Go.

B. The loop condition is wrong.

C. fmt.Println is not imported.

D. The break statement should be continue.

Solution

1. Step 1: Understand break usage in Go

   Go's break does not accept a number to break multiple loops; it only breaks the closest loop.

2. Step 2: Identify invalid syntax

   Using break 2 causes a syntax error because Go does not support labeled breaks with numbers.

3. Final Answer:

   Using break with a number is invalid in Go. -> Option A

4. Quick Check:

   Break with number invalid = Using break with a number is invalid in Go. [OK]

Hint: Go break never takes a number, only plain break [OK]

Common Mistakes:

• Trying to break multiple loops with a number
• Confusing Go with other languages like JavaScript
• Ignoring syntax errors from break usage

5. Given nested loops, how can you use break to exit only the inner loop in Go?

for i := 1; i <= 3; i++ {
    for j := 1; j <= 3; j++ {
        if j == 2 {
            break
        }
        fmt.Printf("%d,%d ", i, j)
    }
}

What will be the output?

hard

A. 1,1 2,1 3,1

B. 1,1 1,2 2,1 2,2 3,1 3,2

C. 1,1 1,2 2,1 2,2 3,1 3,2 2,2 3,2

D. 1,1 1,2 1,3 2,1 2,2 2,3 3,1 3,2 3,3

Solution

1. Step 1: Understand break in nested loops

   The break inside the inner loop stops only that inner loop when j == 2.

2. Step 2: Trace output for each iteration

   For each i, inner loop prints when j=1, then breaks at j=2, so output is pairs with j=1 only.

3. Final Answer:

   1,1 2,1 3,1 -> Option A

4. Quick Check:

   Break stops inner loop only = 1,1 2,1 3,1 [OK]

Hint: Break stops only closest loop, inner loop ends early [OK]

Common Mistakes:

• Thinking break exits both loops
• Expecting all j values printed
• Confusing break with continue