Operator precedence in Javascript - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the output of this code with mixed operators?

Consider the following JavaScript code snippet. What will it print to the console?

Javascript

console.log(3 + 4 * 2 / (1 - 5) ** 2);

A SyntaxError

B 1

C 3.5

D 3.75

💡 Hint

Remember that exponentiation (**) has higher precedence than multiplication and division, which have higher precedence than addition.

The expression evaluates as 3 + (4 * 2) / ((1 - 5) ** 2) = 3 + 8 / 16 = 3 + 0.5 = 3.5.

❓ Predict Output

intermediate

What is the output of this logical and arithmetic expression?

What will the following code output?

Javascript

console.log(true || false && false);

A true

B false

C SyntaxError

D undefined

💡 Hint

Remember that && has higher precedence than ||.

&& is evaluated first: false && false is false, then true || false is true.

❓ Predict Output

advanced

What is the output of this tricky assignment expression?

What will this code print?

Javascript

let a = 1; let b = 2; let c = 3; console.log(a += b *= c);

A 7

B 6

C 9

D TypeError

💡 Hint

Assignment operators are right-associative and have lower precedence than multiplication.

b *= c means b = b * c = 2 * 3 = 6; then a += b means a = a + b = 1 + 6 = 7; console.log prints 7.

❓ Predict Output

advanced

What is the output of this expression with unary and binary operators?

What will the following code output?

Javascript

console.log(-3 ** 2);

A -6

B 9

C SyntaxError

D -9

💡 Hint

Unary minus has lower precedence than exponentiation in JavaScript, so -3 ** 2 is parsed as -(3 ** 2) = -9.

In JavaScript, unary minus has lower precedence than exponentiation, so -3 ** 2 is parsed as -(3 ** 2) = -9.

❓ Predict Output

expert

What is the output of this complex expression mixing bitwise and logical operators?

What will this code print?

Javascript

console.log((5 & 3) || (0 && 2));

A 0

B 1

C 2

D SyntaxError

💡 Hint

Bitwise AND (&) has higher precedence than logical AND (&&) and logical OR (||).

5 & 3 = 1 (bitwise AND), 0 && 2 = 0 (logical AND), then 1 || 0 = 1 (logical OR).