Assignment operators in C++ - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of compound assignment with multiplication

What is the output of this C++ code snippet?

C++

#include <iostream>
int main() {
    int a = 5;
    a *= 3 + 2;
    std::cout << a << std::endl;
    return 0;
}

A Syntax error

B 25

C 15

D 10

💡 Hint

Remember operator precedence: multiplication assignment and addition.

The expression 'a *= 3 + 2;' is evaluated as 'a *= (3 + 2);' because '+' has higher precedence than '*='. So, a = 5 * 5 = 25.

❓ Predict Output

intermediate

Result of chained assignment

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

C++

#include <iostream>
int main() {
    int a, b, c;
    a = b = c = 7;
    c += 3;
    std::cout << c << std::endl;
    return 0;
}

A 7

B 3

C 10

D 0

💡 Hint

Look at the chained assignment and then the addition assignment.

All variables a, b, and c are assigned 7. Then c is increased by 3, so c becomes 10.

❓ Predict Output

advanced

Effect of bitwise assignment operator

What is the output of this C++ program?

C++

#include <iostream>
int main() {
    unsigned int x = 12; // binary 1100
    x >>= 2;
    std::cout << x << std::endl;
    return 0;
}

A 3

B 48

C 6

D Syntax error

💡 Hint

Right shift operator divides by powers of two.

Right shifting 12 (1100 binary) by 2 bits results in 3 (0011 binary).

❓ Predict Output

advanced

Output of combined assignment with logical operators

What is the output of this code snippet?

C++

#include <iostream>
int main() {
    int a = 5;
    a &= 3;
    std::cout << a << std::endl;
    return 0;
}

A 0

B 7

C 1

D 2

💡 Hint

Use bitwise AND on the binary forms of 5 and 3.

5 in binary is 0101, 3 is 0011. Bitwise AND is 0001 which is 1.

🧠 Conceptual

expert

Understanding behavior of assignment in expressions

Consider this code snippet. What is the value of y after execution?

C++

#include <iostream>
int main() {
    int x = 4;
    int y = (x += 3) * 2;
    std::cout << y << std::endl;
    return 0;
}

A 14

B 10

C 8

D 7

💡 Hint

Remember that assignment expressions return the assigned value.

x += 3 changes x to 7 and returns 7. Then y = 7 * 2 = 14.