Logical operators in C Sharp (C#) - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of combined logical operators

What is the output of the following C# code snippet?

C Sharp (C#)

bool a = true;
bool b = false;
bool c = true;
Console.WriteLine(a && b || c);

A True

B False

C Compilation error

D Runtime exception

💡 Hint

Remember the precedence of && and || operators in C#.

The expression a && b || c is evaluated as (a && b) || c. Since a && b is false, and c is true, the overall result is true.

❓ Predict Output

intermediate

Result of negation and OR operator

What will be printed by this C# code?

C Sharp (C#)

bool x = false;
bool y = true;
Console.WriteLine(!x || y);

A False

B Runtime exception

C Compilation error

D True

💡 Hint

Check how the NOT operator affects the value of x.

The NOT operator !x changes false to true. So !x || y becomes true || true, which is true.

❓ Predict Output

advanced

Output with short-circuit evaluation

What is the output of this C# code snippet?

C Sharp (C#)

int i = 0;
bool result = false && (++i > 0);
Console.WriteLine(i);

A Compilation error

B 1

C 0

D Runtime exception

💡 Hint

Consider how the && operator short-circuits evaluation.

Because the first operand is false, the second operand (++i > 0) is not evaluated. So i remains 0.

❓ Predict Output

advanced

Value of variable after complex logical expression

What is the value of variable flag after running this code?

C Sharp (C#)

bool flag = true;
flag = flag && false || !flag && true;
Console.WriteLine(flag);

A Compilation error

B False

C True

D Runtime exception

💡 Hint

Break down the expression into parts and evaluate step by step.

Evaluate flag && false → true && false = false.
Evaluate !flag && true → !true && true = false && true = false.
So overall expression is false || false = false.

🧠 Conceptual

expert

Understanding logical operator precedence and evaluation

Given the expression true || false && false in C#, which statement is correct about its evaluation?

A The expression evaluates to true because && has higher precedence than ||, so false && false is evaluated first.

B The expression evaluates to false because || has higher precedence than &&, so true || false is evaluated first.

C The expression causes a runtime error due to ambiguous operator precedence.

D The expression evaluates to false because both operators have the same precedence and are evaluated left to right.

💡 Hint

Recall operator precedence rules in C# for logical operators.

In C#, the && operator has higher precedence than ||. So false && false is evaluated first, resulting in false. Then true || false is evaluated, resulting in true.