Logical operators in Go - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to check if both conditions are true.

Go

if a > 0 [1] b < 10 {
    fmt.Println("Both conditions are true")
}

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 negates a condition

The && operator checks if both conditions are true.

2fill in blank

medium

Complete the code to check if at least one condition is true.

Go

if x == 5 [1] y == 10 {
    fmt.Println("At least one condition is true")
}

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

A||

B&&

C!=

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using && which requires both conditions

Using == which compares equality

The || operator means 'or' and returns true if either condition is true.

3fill in blank

hard

Fix the error in the condition to negate the check.

Go

if [1] {
    fmt.Println("Flag is false")
}

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

Aflag

Bflag = false

Cflag == true

D!flag

Attempts:

3 left

💡 Hint

Common Mistakes

Using assignment = instead of comparison

Not negating the flag

The !flag negates the boolean value of flag.

4fill in blank

hard

Fill both blanks to check if number is between 10 and 20 (inclusive).

Go

if num [1]= 10 [2] num <= 20 {
    fmt.Println("Number is between 10 and 20")
}

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

A>

B<

C&&

D||

Attempts:

3 left

💡 Hint

Common Mistakes

Using < instead of >

Using || instead of &&

Use num >= 10 and && to combine conditions.

5fill in blank

hard

Fill all three blanks to check if value is outside the range 1 to 5.

Go

if value [1] 1 [2] value [3] 5 {
    fmt.Println("Value is outside 1 to 5")
}

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

A<

B>

C||

D&&

Attempts:

3 left

💡 Hint

Common Mistakes

Using && which means both conditions must be true

Swapping < and > signs

Use value < 1 or value > 5 combined with || to check outside the range.

Practice

1. Which logical operator in Go means AND and returns true only if both conditions are true?

easy

A. !

B. ||

C. &

D. &&

Solution

1. Step 1: Understand the meaning of logical AND

   The AND operator returns true only when both conditions it connects are true.

2. Step 2: Identify Go's AND operator

   In Go, the AND operator is written as &&, which matches the description.

3. Final Answer:

   && -> Option D

4. Quick Check:

   AND = && [OK]

Hint: AND is &&, OR is ||, NOT is ! [OK]

Common Mistakes:

• Confusing & (bitwise AND) with && (logical AND)
• Mixing OR (||) with AND (&&)
• Using ! as AND operator

2. Which of the following is the correct syntax for the logical NOT operator in Go?

easy

A. not x

B. !x

C. ~x

D. x!

Solution

1. Step 1: Recall Go syntax for logical NOT

   In Go, the logical NOT operator is a single exclamation mark placed before the variable or expression.

2. Step 2: Match options with correct syntax

   !x uses !x, which is the correct syntax for NOT in Go.

3. Final Answer:

   !x -> Option B

4. Quick Check:

   NOT = ! [OK]

Hint: NOT always uses ! before the condition [OK]

Common Mistakes:

• Writing 'not x' like in some other languages
• Using ~ which is bitwise NOT, not logical NOT
• Placing ! after the variable

3. What is the output of this Go code snippet?

package main
import "fmt"
func main() {
    a := true
    b := false
    fmt.Println(a && !b || b)
}

medium

A. true

B. false

C. Syntax error

D. Compilation error

Solution

1. Step 1: Evaluate !b

   b is false, so !b is true.

2. Step 2: Evaluate a && !b

   a is true and !b is true, so a && !b is true.

3. Step 3: Evaluate (a && !b) || b

   true || false is true.

4. Final Answer:

   true -> Option A

5. Quick Check:

   True AND NOT False OR False = True [OK]

Hint: Evaluate NOT first, then AND, then OR [OK]

Common Mistakes:

• Evaluating OR before AND
• Forgetting to negate b
• Assuming false || true is false

4. Identify the error in this Go code snippet:

package main
import "fmt"
func main() {
    x := true
    y := false
    if x & y {
        fmt.Println("Both true")
    }
}

medium

A. Using & instead of && in if condition

B. Missing parentheses around condition

C. fmt.Println syntax error

D. Variable declaration error

Solution

1. Step 1: Check logical operators in if condition

   The code uses & which is bitwise AND, not logical AND.

2. Step 2: Identify correct operator for boolean logic

   Logical AND in Go is &&, so & causes a type error here.

3. Final Answer:

   Using & instead of && in if condition -> Option A

4. Quick Check:

   Logical AND needs &&, not & [OK]

Hint: Use && for logical AND, & is bitwise [OK]

Common Mistakes:

• Using & instead of && for booleans
• Assuming & works like && in conditions
• Ignoring compiler error messages

5. Given a variable score (int), which condition correctly checks if score is between 50 and 100 inclusive using logical operators in Go?

hard

A. score >= 50 || score <= 100

B. score > 50 && score < 100

C. score >= 50 && score <= 100

D. score > 50 || score < 100

Solution

1. Step 1: Understand the range condition

   We want score to be at least 50 and at most 100, so both conditions must be true.

2. Step 2: Choose correct logical operator

   AND (&&) combines conditions that both must be true; OR (||) would allow values outside the range.

3. Step 3: Check inclusivity

   Using >= and <= includes 50 and 100 themselves.

4. Final Answer:

   score >= 50 && score <= 100 -> Option C

5. Quick Check:

   Between means AND, not OR [OK]

Hint: Use && to combine conditions that both must be true [OK]

Common Mistakes:

• Using || which allows values outside range
• Using > and < excludes boundary values
• Confusing AND and OR logic