Chapter 6 Beginner 57 Questions

Practice Questions — Conditional Statements (if, else, switch)

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11 Easy

12 Medium

10 Hard

Topic-Specific Questions

Question 1

Easy

What is the output?

int x = 10;
if (x > 5) {
    cout << "Yes";
}

Check if 10 > 5.

Yes

Question 2

Easy

What is the output?

int a = 3, b = 7;
if (a > b) {
    cout << a;
} else {
    cout << b;
}

Compare 3 and 7.

7

Question 3

Easy

What is the output?

int num = 0;
if (num) {
    cout << "Truthy";
} else {
    cout << "Falsy";
}

In C++, what is the truthiness of 0?

Falsy

Question 4

Easy

What is the output?

int x = 15;
if (x >= 10 && x <= 20) {
    cout << "In range";
} else {
    cout << "Out of range";
}

Check if 15 is between 10 and 20 inclusive.

In range

Question 5

Easy

What is the output?

int a = 5, b = 10;
int result = (a > b) ? a : b;
cout << result;

Ternary: if condition is false, the value after : is used.

10

Question 6

Easy

What is the output?

char ch = 'B';
switch (ch) {
    case 'A': cout << "Alpha"; break;
    case 'B': cout << "Beta"; break;
    case 'C': cout << "Gamma"; break;
    default: cout << "Unknown";
}

ch is 'B', find the matching case.

Beta

Question 7

Medium

What is the output?

int x = 5;
if (x = 0) {
    cout << "Zero";
} else {
    cout << "Not zero";
}

Notice the single = sign in the condition.

Not zero

Question 8

Medium

What is the output?

int day = 3;
switch (day) {
    case 1: cout << "Mon ";
    case 2: cout << "Tue ";
    case 3: cout << "Wed ";
    case 4: cout << "Thu ";
            break;
    case 5: cout << "Fri ";
}

No break after case 3. What happens?

Wed Thu

Question 9

Medium

What is the output?

int a = 10, b = 20, c = 15;
if (a > b) {
    if (a > c) cout << a;
    else cout << c;
} else {
    if (b > c) cout << b;
    else cout << c;
}

This finds the maximum of three numbers.

20

Question 10

Medium

What is the output?

int x = 5;
if (x > 10);
{
    cout << "Hello";
}

Notice the semicolon after the if condition.

Hello

Question 11

Medium

What is the output?

int marks = 75;
if (marks >= 90)
    cout << "A";
else if (marks >= 80)
    cout << "B";
else if (marks >= 70)
    cout << "C";
else
    cout << "D";

Check conditions top to bottom. Which is the first to be true?

C

Question 12

Medium

What is the output?

int x = -5;
int abs = (x >= 0) ? x : -x;
cout << abs;

x is negative. Which branch of the ternary is taken?

5

Question 13

Hard

What is the output?

int a = 1, b = 0;
if (a > 0)
    if (b > 0)
        cout << "Both positive";
else
    cout << "Not both positive";

Dangling else: which if does the else bind to?

Not both positive

Question 14

Hard

What is the output?

int x = 3;
switch (x) {
    default: cout << "D ";
    case 1: cout << "1 "; break;
    case 2: cout << "2 ";
    case 3: cout << "3 ";
}

default does not have to be at the end. And case 3 has no break.

3

Question 15

Hard

What is the output?

int x = 5;
switch (x) {
    default: cout << "D ";
    case 1: cout << "1 "; break;
    case 2: cout << "2 ";
}

No case matches x = 5. Where does execution start?

D 1

Question 16

Hard

What is the output?

int a = 5, b = 3;
cout << ((a > b) ? (a - b) : (b - a)) << endl;
cout << ((a < b) ? (a - b) : (b - a)) << endl;

Evaluate each ternary condition separately.

2
-2

Question 17

Easy

In C++, what values are considered truthy and falsy when used in an if condition?

Think about zero versus non-zero.

In C++, 0 is falsy and every non-zero value is truthy. This includes negative numbers: if (-1) is true. For pointers, nullptr (which is 0) is falsy, and any valid pointer is truthy.

Question 18

Medium

What is the dangling else problem in C++? How do you avoid it?

Think about which if an else binds to when there are no braces.

The dangling else problem occurs when an else could associate with more than one if statement. C++ resolves it by binding else to the nearest unmatched if, regardless of indentation. To avoid ambiguity, always use curly braces {} around if and else bodies, even for single statements.

Question 19

Hard

Why can you not use a string or a floating-point number in a switch expression in C++?

Think about how switch is implemented at the machine level.

The switch statement is typically compiled into a jump table or binary search on case values, both of which require integral (integer/char/enum) constants for efficient comparison. Floating-point numbers have precision issues (0.1 + 0.2 != 0.3), making exact comparison unreliable. Strings are objects, not integral types, and comparing them requires calling functions rather than simple integer comparison.

Question 20

Hard

What is the output?

int x = 2;
int y = (x > 0) - (x < 0);
cout << y;

Boolean expressions evaluate to 0 or 1 in C++.

1

Mixed & Application Questions

Question 1

Easy

Write a program that takes an integer and prints whether it is positive, negative, or zero.

Use if-else if-else with two conditions.

#include 
using namespace std;
int main() {
    int n;
    cin >> n;
    if (n > 0) cout << "Positive" << endl;
    else if (n < 0) cout << "Negative" << endl;
    else cout << "Zero" << endl;
    return 0;
}

Question 2

Easy

What is the output?

int a = 10;
if (a == 10)
    cout << "Ten ";
cout << "Done";

Without braces, only the first statement after if is in the body.

Ten Done

Question 3

Easy

What is the output?

int x = 7;
if (x > 5 && x < 10)
    cout << "Yes";
else
    cout << "No";

Is 7 greater than 5 AND less than 10?

Yes

Question 4

Medium

What is the output?

int x = 5;
if (x > 3)
    if (x > 10)
        cout << "A";
    else
        cout << "B";
else
    cout << "C";

Apply the dangling else rule carefully.

B

Question 5

Medium

Write a program that takes a character and checks if it is a vowel or consonant (assume lowercase English letters only).

Use switch-case with fall-through for the 5 vowels.

#include 
using namespace std;
int main() {
    char ch;
    cin >> ch;
    switch (ch) {
        case 'a': case 'e': case 'i': case 'o': case 'u':
            cout << ch << " is a vowel" << endl;
            break;
        default:
            cout << ch << " is a consonant" << endl;
    }
    return 0;
}

Question 6

Medium

What is the output?

int a = 5, b = 10, c = 5;
if (a == c)
    cout << "A ";
if (a == b)
    cout << "B ";
if (b != c)
    cout << "C ";

These are three separate if statements, not if-else if.

A C

Question 7

Medium

What is the output?

int x = 10;
if (x > 5 || x < 3) {
    cout << "Yes";
} else {
    cout << "No";
}

With ||, if the first condition is true, the whole expression is true.

Yes

Question 8

Hard

What is the output?

int a = 2, b = 3, c = 4;
int result = (a > b) ? a : (b > c) ? b : c;
cout << result;

Evaluate the outer ternary first, then the nested one.

4

Question 9

Hard

What is the output?

int x = 0;
switch (x) {
    case 0:
        cout << "Zero ";
    case 1:
        cout << "One ";
    default:
        cout << "Default ";
}

No break statements anywhere. What happens after case 0 matches?

Zero One Default

Question 10

Easy

Write a program that checks if a given year is a leap year.

Leap if divisible by 4, but not 100, unless also divisible by 400.

#include 
using namespace std;
int main() {
    int year;
    cin >> year;
    if ((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0))
        cout << year << " is a leap year" << endl;
    else
        cout << year << " is not a leap year" << endl;
    return 0;
}

Question 11

Hard

What is the output?

int a = 5;
if (a > 2)
    cout << "A ";
if (a > 3)
    cout << "B ";
if (a > 4)
    cout << "C ";
if (a > 5)
    cout << "D ";

Each if is independent. Check all four conditions.

A B C

Question 12

Medium

Write a program that takes three integers and prints them in ascending order using only if-else statements (no arrays or sorting algorithms).

Compare pairs and rearrange using swaps or nested conditions.

#include 
using namespace std;
int main() {
    int a, b, c;
    cin >> a >> b >> c;
    if (a > b) { int t = a; a = b; b = t; }
    if (b > c) { int t = b; b = c; c = t; }
    if (a > b) { int t = a; a = b; b = t; }
    cout << a << " " << b << " " << c << endl;
    return 0;
}

Question 13

Hard

What is the output?

int x = 1;
if (x)
    if (x - 1)
        cout << "A";
    else
        cout << "B";
else
    cout << "C";

x is 1 (truthy). x-1 is 0 (falsy). Apply the dangling else rule.

B

Multiple Choice Questions

MCQ 1

What is the output of if (0) cout << "Yes"; else cout << "No";?

A. Yes
B. No
C. Compilation error
D. No output

Answer: B
B is correct. In C++, 0 is falsy. The condition is false, so the else block executes and prints No.

MCQ 2

Which of the following is the correct ternary operator syntax in C++?

A. condition ? true : false
B. condition : true ? false
C. if condition then true else false
D. condition ?? true : false

Answer: A
A is correct. The ternary syntax is condition ? value_if_true : value_if_false.

MCQ 3

What happens when no case matches in a switch and there is no default?

A. Compilation error
B. Runtime error
C. The switch block is skipped entirely
D. The first case executes

Answer: C
C is correct. If no case matches and there is no default, the entire switch body is skipped. No error occurs.

MCQ 4

Which data types can be used in a switch expression in C++?

A. int, char, float
B. int, char, string
C. int, char, enum
D. Any data type

Answer: C
C is correct. switch requires an integral or enumeration type: int, char, short, long, bool, or enum. float, double, and string are not allowed.

MCQ 5

In C++, what is the value of the expression (5 > 3)?

A. true
B. 1
C. 5
D. Both A and B

Answer: D
D is correct. In C++, a boolean true has the integer value 1. The expression (5 > 3) evaluates to true, which is 1 when used in an integer context.

MCQ 6

What is the output?
int x = 5; if (x = 10) cout << x; else cout << 0;

A. 5
B. 10
C. 0
D. Compilation error

Answer: B
B is correct. x = 10 is an assignment, not comparison. It assigns 10 to x and returns 10, which is truthy. So the if body runs and prints x, which is now 10.

MCQ 7

In the dangling else problem, the else binds to:

A. The first if in the code
B. The if matching the indentation
C. The nearest unmatched if
D. It causes a compilation error

Answer: C
C is correct. C++ ignores indentation. The else always associates with the nearest preceding if that does not already have an else.

MCQ 8

What does the break statement do inside a switch-case?

A. Exits the program
B. Exits the current function
C. Exits the switch block
D. Skips to the default case

Answer: C
C is correct. break exits the switch block entirely, preventing fall-through to subsequent cases.

MCQ 9

What is the output?
int x = 3; switch(x) { case 1: case 2: case 3: cout << "Low"; break; case 4: case 5: cout << "High"; break; }

A. Low
B. High
C. LowHigh
D. No output

Answer: A
A is correct. x is 3, which matches case 3. Cases 1, 2, 3 are grouped via fall-through. The break after cout << "Low" prevents further execution.

MCQ 10

Which of the following is an infinite loop caused by a conditional bug?

A. if (true) {}
B. while (x = 1) { x++; }
C. for (int i=0; i<10; i++) {}
D. switch(1) { default: break; }

Answer: B
B is correct. x = 1 is an assignment (not comparison). It assigns 1 to x every iteration and returns 1 (truthy), so the loop never ends. The x++ has no effect because x is reset to 1 at the start of each check.

MCQ 11

What is the output?
int a = 0, b = 0; if (a++ && ++b) cout << a << b; else cout << a << b;

A. 00
B. 10
C. 11
D. 01

Answer: B
B is correct. a++ returns 0 (post-increment: uses old value), which is falsy. Due to short-circuit evaluation, ++b is never executed. After the expression, a is 1 (incremented) and b is 0 (never touched). The else branch prints 10.

MCQ 12

What is the output?
int x = 10; int y = (x > 5) ? (x < 15) ? 1 : 2 : 3; cout << y;

A. 1
B. 2
C. 3
D. Compilation error

Answer: A
A is correct. Outer ternary: x > 5 (true), so evaluate inner ternary: x < 15 (true), returns 1. y = 1.

MCQ 13

What is the value of z?
int x = 5, y = 10; int z = (x > 0) + (y > 0) + (x + y > 0);

A. 0
B. 1
C. 3
D. Compilation error

Answer: C
C is correct. Each boolean expression evaluates to 1 (true): (5>0)=1, (10>0)=1, (15>0)=1. Sum: 1+1+1=3. This exploits boolean-to-integer conversion in C++.

MCQ 14

Can the default case appear before other cases in a switch block?

A. No, it must be the last case
B. Yes, and it works correctly
C. Yes, but it causes undefined behavior
D. Only if there are no other cases

Use if-else if with character ranges ('A'-'Z', 'a'-'z', '0'-'9'). Do not use library functions like isupper().

#include <iostream>
using namespace std;
int main() {
    char ch;
    cout << "Enter a character: ";
    cin >> ch;
    cout << ch << " is ";
    if (ch >= 'A' && ch <= 'Z')
        cout << "an uppercase letter";
    else if (ch >= 'a' && ch <= 'z')
        cout << "a lowercase letter";
    else if (ch >= '0' && ch <= '9')
        cout << "a digit";
    else if (ch == ' ' || ch == '\t' || ch == '\n')
        cout << "a whitespace character";
    else
        cout << "a special character";
    cout << " (ASCII: " << (int)ch << ")" << endl;
    return 0;
}

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