If statement in Go - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to check if x is greater than 10.

Go

if x [1] 10 {
    fmt.Println("x is greater than 10")
}

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

A<

B<=

C==

D>

Attempts:

3 left

💡 Hint

Common Mistakes

Using < instead of >

Using == which checks equality, not greater than

The greater than operator > checks if x is more than 10.

2fill in blank

medium

Complete the code to print "Even" if number is divisible by 2.

Go

if number [1] 2 == 0 {
    fmt.Println("Even")
}

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

A*

B+

C%

D-

Attempts:

3 left

💡 Hint

Common Mistakes

Using + or - instead of %

Using * which multiplies numbers

The modulus operator % gives the remainder. If remainder is 0 when divided by 2, the number is even.

3fill in blank

hard

Fix the error in the if statement to check if age is at least 18.

Go

if age [1] 18 {
    fmt.Println("Adult")
}

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

A>=

B<

C<=

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using < or <= which check less than

Using == which checks exact equality

The operator >= means 'greater than or equal to', so it checks if age is 18 or more.

4fill in blank

hard

Fill both blanks to print "Valid" if score is between 50 and 100 inclusive.

Go

if score [1] 50 && score [2] 100 {
    fmt.Println("Valid")
}

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

A>=

B<

C<=

D>

Attempts:

3 left

💡 Hint

Common Mistakes

Using > or < which exclude boundary values

Mixing up the order of operators

The condition checks if score is at least 50 (>=) and at most 100 (<=).

5fill in blank

hard

Fill all three blanks to create a map of words to their lengths for words longer than 3 characters.

Go

lengths := map[string]int{}
for _, [3] := range words {
    if len([3]) > 3 {
        lengths[[1]] = [2]
    }
}

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

Aword

Blen(word)

Dw

Attempts:

3 left

💡 Hint

Common Mistakes

Using different variable names inconsistently

Using wrong expressions for length

The map uses the word as key and its length as value. The loop variable is word.

Practice

1. What does an if statement do in Go?

easy

A. It runs code only if a condition is true.

B. It repeats code multiple times.

C. It stores data in a variable.

D. It defines a new function.

Solution

1. Step 1: Understand the purpose of an if statement

   An if statement checks a condition and runs code only when that condition is true.

2. Step 2: Compare options with the if statement behavior

   Only "It runs code only if a condition is true." describes running code based on a condition being true.

3. Final Answer:

   It runs code only if a condition is true. -> Option A

4. Quick Check:

   If statement = runs code if true [OK]

Hint: If checks true/false to decide running code [OK]

Common Mistakes:

• Confusing if with loops
• Thinking if stores data
• Mixing if with function definitions

2. Which of these is the correct syntax for an if statement in Go?

easy

A. if (x > 10) then { fmt.Println("Big") }

B. if x > 10 { fmt.Println("Big") }

C. if x > 10: fmt.Println("Big")

D. if x > 10 { fmt.Println("Big") else }

Solution

1. Step 1: Recall Go if statement syntax

   Go uses if condition { code } without parentheses or 'then'.

2. Step 2: Check each option

   if x > 10 { fmt.Println("Big") } matches Go syntax exactly. Options A, C, and D have syntax errors.

3. Final Answer:

   if x > 10 { fmt.Println("Big") } -> Option B

4. Quick Check:

   Go if syntax = if condition { } [OK]

Hint: Go if uses braces, no 'then' or colons [OK]

Common Mistakes:

• Adding 'then' keyword
• Using parentheses around condition
• Using colon instead of braces

3. What is the output of this Go code?

package main
import "fmt"
func main() {
  x := 5
  if x > 3 {
    fmt.Println("Yes")
  } else {
    fmt.Println("No")
  }
}

medium

A. Syntax error

B. No

C. 5

D. Yes

Solution

1. Step 1: Check the condition in the if statement

   The variable x is 5, and the condition is x > 3, which is true.

2. Step 2: Determine which block runs

   Since the condition is true, the code inside the if block runs, printing "Yes".

3. Final Answer:

   Yes -> Option D

4. Quick Check:

   x=5 > 3 is true, prints "Yes" [OK]

Hint: If condition true runs if-block, else runs else-block [OK]

Common Mistakes:

• Confusing which block runs
• Thinking it prints the variable
• Assuming syntax error due to else

4. Find the error in this Go code:

package main
import "fmt"
func main() {
  x := 10
  if x > 5
    fmt.Println("Big")
}

medium

A. Variable x not declared

B. Missing semicolon after x := 10

C. Missing braces { } after if condition

D. Wrong import statement

Solution

1. Step 1: Check if statement syntax

   In Go, the if condition must be followed by braces { } to group the code.

2. Step 2: Identify the missing part

   The code after if lacks braces, causing a syntax error.

3. Final Answer:

   Missing braces { } after if condition -> Option C

4. Quick Check:

   If needs braces { } after condition [OK]

Hint: Always use braces { } after if condition [OK]

Common Mistakes:

• Omitting braces after if
• Adding unnecessary semicolons
• Misunderstanding import errors

5. You want to print "Positive", "Zero", or "Negative" based on an integer variable n. Which code correctly uses if statements to do this?

hard

A. if n > 0 { fmt.Println("Positive") } else if n == 0 { fmt.Println("Zero") } else { fmt.Println("Negative") }

B. if n > 0 { fmt.Println("Positive") } if n == 0 { fmt.Println("Zero") } else { fmt.Println("Negative") }

C. if n > 0 { fmt.Println("Positive") } else if n <= 0 { fmt.Println("Negative") } else { fmt.Println("Zero") }

D. if n >= 0 { fmt.Println("Positive") } else if n == 0 { fmt.Println("Zero") } else { fmt.Println("Negative") }

Solution

1. Step 1: Understand the conditions for each case

   Positive means n > 0, zero means n == 0, negative means n < 0.

2. Step 2: Check each option's logic

   if n > 0 { fmt.Println("Positive") } else if n == 0 { fmt.Println("Zero") } else { fmt.Println("Negative") } correctly checks n > 0, then n == 0, else negative. if n > 0 { fmt.Println("Positive") } if n == 0 { fmt.Println("Zero") } else { fmt.Println("Negative") } has two separate ifs causing multiple prints. if n > 0 { fmt.Println("Positive") } else if n <= 0 { fmt.Println("Negative") } else { fmt.Println("Zero") } swaps zero and negative logic. if n >= 0 { fmt.Println("Positive") } else if n == 0 { fmt.Println("Zero") } else { fmt.Println("Negative") } wrongly treats n >= 0 as positive.

3. Final Answer:

   if n > 0 { fmt.Println("Positive") } else if n == 0 { fmt.Println("Zero") } else { fmt.Println("Negative") } -> Option A

4. Quick Check:

   Correct if-else chain matches conditions [OK]

Hint: Use else if to check exclusive conditions in order [OK]

Common Mistakes:

• Using multiple ifs causing multiple outputs
• Mixing condition order
• Wrong comparison operators