Conditional statements allow a program to make decisions based on certain conditions. They help control the flow of execution by executing different blocks of code depending on whether a condition is true or false.

Video Explanation​

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Types of Conditional Statements​

1. if Statement​

The if statement executes a block of code if the specified condition evaluates to true.

Syntax:

if (condition) {
    // Code to execute if condition is true
}

Example:

int age = 18;
if (age >= 18) {
    cout << "You are eligible to vote." << endl;
}

2. if-else Statement​

The if-else statement provides an alternative block of code to execute if the condition is false.

Syntax:

if (condition) {
    // Code to execute if condition is true
} else {
    // Code to execute if condition is false
}

Example:

int age = 16;
if (age >= 18) {
    cout << "You are eligible to vote." << endl;
} else {
    cout << "You are not eligible to vote." << endl;
}

3. if-else if-else Ladder​

This structure allows you to test multiple conditions sequentially. The first true condition will be executed.

Syntax:

if (condition1) {
    // Code for condition1
} else if (condition2) {
    // Code for condition2
} else {
    // Code if none of the conditions are true
}

Example:

int marks = 75;
if (marks >= 90) {
    cout << "Grade: A" << endl;
} else if (marks >= 75) {
    cout << "Grade: B" << endl;
} else {
    cout << "Grade: C" << endl;
}

4. Nested if Statement​

An if statement inside another if statement. This is useful for checking multiple related conditions.

Syntax:

if (condition1) {
    if (condition2) {
        // Code if both conditions are true
    }
}

Example:

int age = 20;
bool hasID = true;
if (age >= 18) {
    if (hasID) {
        cout << "You are allowed entry." << endl;
    }
}

5. switch Statement​

The switch statement is used when you have multiple conditions based on a single variable.

Syntax:

switch (expression) {
    case value1:
        // Code for value1
        break;
    case value2:
        // Code for value2
        break;
    default:
        // Code if no case matches
}

Example:

int day = 3;
switch (day) {
    case 1:
        cout << "Monday" << endl;
        break;
    case 2:
        cout << "Tuesday" << endl;
        break;
    case 3:
        cout << "Wednesday" << endl;
        break;
    default:
        cout << "Invalid day" << endl;
}

When to Use Each Conditional Statement​

• if Statement: When you need to check a single condition.
• if-else Statement: When there are two possibilities (true/false).
• if-else if-else Ladder: When there are multiple conditions to evaluate sequentially.
• Nested if: When conditions depend on each other.
• switch Statement: When you have multiple values for a single variable.

Conclusion​

Conditional statements are essential for controlling the flow of a program. Understanding when and how to use each type of conditional statement is crucial for writing efficient and logical code.