Flow Control

1. Flow Control

Flow control in C++ refers to the order in which statements are executed. It includes:

• Conditional Statements: if, else if, else, and switch.

• Loops: for, while, and do-while.

• Jump Statements: break, continue, and return.

Example:

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int x = 10;
if (x > 5) {
    cout << "x is greater than 5" << endl;
} else {
    cout << "x is less than or equal to 5" << endl;
}

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2. Hello World

The classic "Hello World" program in C++:

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#include <iostream>
using namespace std;

int main() {
    cout << "Hello, World!" << endl;
    return 0;
}

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3. Input From User in C++

To take input from the user, use cin:

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#include <iostream>
using namespace std;

int main() {
    int number;
    cout << "Enter a number: ";
    cin >> number;
    cout << "You entered: " << number << endl;
    return 0;
}

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4. Arithmetic Operators in C++

Arithmetic operators perform mathematical operations:

• + (addition)

• - (subtraction)

• * (multiplication)

• / (division)

• % (modulus)

Example:

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int a = 10, b = 3;
cout << "Sum: " << a + b << endl;
cout << "Difference: " << a - b << endl;
cout << "Product: " << a * b << endl;
cout << "Quotient: " << a / b << endl;
cout << "Remainder: " << a % b << endl;

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5. Assignment Operators in C++

Assignment operators are used to assign values to variables:

• = (simple assignment)

• +=, -=, *=, /=, %= (compound assignment)

Example:

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int x = 5;
x += 3; // Equivalent to x = x + 3
cout << "x: " << x << endl;

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6. Comparison Operators in C++

Comparison operators compare two values:

• == (equal to)

• != (not equal to)

• > (greater than)

• < (less than)

• >= (greater than or equal to)

• <= (less than or equal to)

Example:

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int a = 5, b = 10;
if (a == b) {
    cout << "a and b are equal" << endl;
} else {
    cout << "a and b are not equal" << endl;
}

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7. Logical Operators in C++

Logical operators are used to combine multiple conditions:

• && (logical AND)

• || (logical OR)

• ! (logical NOT)

Example:

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int age = 20;
bool isStudent = true;

if (age >= 18 && isStudent) {
    cout << "You are an adult student." << endl;
}

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8. Math Functions in C++

C++ provides math functions in the <cmath> library:

• sqrt(): Square root

• pow(): Power

• abs(): Absolute value

• sin(), cos(), tan(): Trigonometric functions

• log(), log10(): Logarithmic functions

Example:

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#include <iostream>
#include <cmath>
using namespace std;

int main() {
    double num = 25.0;
    cout << "Square root: " << sqrt(num) << endl;
    cout << "2^3: " << pow(2, 3) << endl;
    return 0;
}

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Let me know if you need further clarification or examples!