Write a simple C++ program to print "Hello, World!".
#include
int main() {
std::cout << "Hello, World!" << std::endl;
return 0;
}
Perform basic arithmetic operations (addition, subtraction, multiplication, division).
#include
int main() {
int a, b;
std::cout << "Enter two numbers: ";
std::cin >> a >> b;
std::cout << "Addition: " << a + b << std::endl;
std::cout << "Subtraction: " << a - b << std::endl;
std::cout << "Multiplication: " << a * b << std::endl;
std::cout << "Division: " << a / b << std::endl;
return 0;
}
Display the size of different data types in C++.
#include
int main() {
std::cout << "Size of int: " << sizeof(int) << " bytes" << std::endl;
std::cout << "Size of float: " << sizeof(float) << " bytes" << std::endl;
std::cout << "Size of double: " << sizeof(double) << " bytes" << std::endl;
std::cout << "Size of char: " << sizeof(char) << " bytes" << std::endl;
return 0;
}
Calculate the area of a circle given its radius.
#include
#define PI 3.14159
int main() {
float radius, area;
std::cout << "Enter the radius of the circle: ";
std::cin >> radius;
area = PI * radius * radius;
std::cout << "Area of the circle: " << area << std::endl;
return 0;
}
Convert temperature from Celsius to Fahrenheit.
#include
int main() {
float celsius, fahrenheit;
std::cout << "Enter temperature in Celsius: ";
std::cin >> celsius;
fahrenheit = (celsius * 9 / 5) + 32;
std::cout << "Temperature in Fahrenheit: " << fahrenheit << std::endl;
return 0;
}
Check if a number is even or odd.
#include
int main() {
int num;
std::cout << "Enter an integer: ";
std::cin >> num;
if (num % 2 == 0) {
std::cout << num << " is even." << std::endl;
} else {
std::cout << num << " is odd." << std::endl;
}
return 0;
}
Find the largest of three numbers.
#include
int main() {
int a, b, c;
std::cout << "Enter three numbers: ";
std::cin >> a >> b >> c;
if (a >= b && a >= c) {
std::cout << "The largest number is: " << a << std::endl;
} else if (b >= a && b >= c) {
std::cout << "The largest number is: " << b << std::endl;
} else {
std::cout << "The largest number is: " << c << std::endl;
}
return 0;
}
Create a simple calculator using switch-case.
#include
int main() {
char op;
float num1, num2;
std::cout << "Enter operator (+, -, *, /): ";
std::cin >> op;
std::cout << "Enter two operands: ";
std::cin >> num1 >> num2;
switch (op) {
case '+':
std::cout << num1 << " + " << num2 << " = " << num1 + num2 << std::endl;
break;
case '-':
std::cout << num1 << " - " << num2 << " = " << num1 - num2 << std::endl;
break;
case '*':
std::cout << num1 << " * " << num2 << " = " << num1 * num2 << std::endl;
break;
case '/':
if (num2 != 0) {
std::cout << num1 << " / " << num2 << " = " << num1 / num2 << std::endl;
} else {
std::cout << "Division by zero error!" << std::endl;
}
break;
default:
std::cout << "Invalid operator!" << std::endl;
break;
}
return 0;
}
Calculate the sum of first N natural numbers using a loop.
#include
int main() {
int n, sum = 0;
std::cout << "Enter a positive integer: ";
std::cin >> n;
for (int i = 1; i <= n; ++i) {
sum += i;
}
std::cout << "Sum of first " << n << " natural numbers is: " << sum << std::endl;
return 0;
}
Print the multiplication table of a given number.
#include
int main() {
int num;
std::cout << "Enter a positive integer: ";
std::cin >> num;
for (int i = 1; i <= 10; ++i) {
std::cout << num << " * " << i << " = " << num * i << std::endl;
}
return 0;
}
Calculate the factorial of a number using a function.
#include
int factorial(int n) {
if (n == 0) return 1;
return n * factorial(n - 1);
}
int main() {
int num;
std::cout << "Enter a positive integer: ";
std::cin >> num;
std::cout << "Factorial of " << num << " is: " << factorial(num) << std::endl;
return 0;
}
Check if a number is prime using a function.
#include
bool isPrime(int n) {
if (n <= 1) return false;
for (int i = 2; i <= n / 2; ++i) {
if (n % i == 0) return false;
}
return true;
}
int main() {
int num;
std::cout << "Enter a positive integer: ";
std::cin >> num;
if (isPrime(num)) {
std::cout << num << " is a prime number." << std::endl;
} else {
std::cout << num << " is not a prime number." << std::endl;
}
return 0;
}
Find the greatest common divisor (GCD) of two numbers using a function.
#include
int gcd(int a, int b) {
if (b == 0) return a;
return gcd(b, a % b);
}
int main() {
int num1, num2;
std::cout << "Enter two positive integers: ";
std::cin >> num1 >> num2;
std::cout << "GCD of " << num1 << " and " << num2 << " is: " << gcd(num1, num2) << std::endl;
return 0;
}
Print the Fibonacci sequence up to N terms using a function.
#include
void printFibonacci(int n) {
int t1 = 0, t2 = 1, nextTerm = 0;
for (int i = 1; i <= n; ++i) {
if (i == 1) {
std::cout << t1 << " ";
continue;
}
if (i == 2) {
std::cout << t2 << " ";
continue;
}
nextTerm = t1 + t2;
t1 = t2;
t2 = nextTerm;
std::cout << nextTerm << " ";
}
}
int main() {
int num;
std::cout << "Enter the number of terms: ";
std::cin >> num;
std::cout << "Fibonacci Series: ";
printFibonacci(num);
std::cout << std::endl;
return 0;
}
Find the sum of digits of a number using a function.
#include
sumOfDigits(int n) {
int sum = 0;
while (n != 0) {
sum += n % 10;
n /= 10;
}
return sum;
}
int main() {
int num;
std::cout << "Enter a positive integer: ";
std::cin >> num;
std::cout << "Sum of digits of " << num << " is: " << sumOfDigits(num) << std::endl;
return 0;
}
Calculate the sum of all elements in an array.
#include
int main() {
int n, sum = 0;
std::cout << "Enter the number of elements: ";
std::cin >> n;
int arr[n];
std::cout << "Enter the elements of the array: ";
for (int i = 0; i < n; ++i) {
std::cin >> arr[i];
sum += arr[i];
}
std::cout << "Sum of array elements: " << sum << std::endl;
return 0;
}
Reverse the elements of an array.
#include
int main() {
int n;
std::cout << "Enter the number of elements: ";
std::cin >> n;
int arr[n];
std::cout << "Enter the elements of the array: ";
for (int i = 0; i < n; ++i) {
std::cin >> arr[i];
}
std::cout << "Reversed array: ";
for (int i = n - 1; i >= 0; --i) {
std::cout << arr[i] << " ";
}
std::cout << std::endl;
return 0;
}
Find the largest element in an array.
#include
int main() {
int n;
std::cout << "Enter the number of elements: ";
std::cin >> n;
int arr[n];
std::cout << "Enter the elements of the array: ";
for (int i = 0; i < n; ++i) {
std::cin >> arr[i];
}
int largest = arr[0];
for (int i = 1; i < n; ++i) {
if (arr[i] > largest) {
largest = arr[i];
}
}
std::cout << "The largest element in the array is: " << largest << std::endl;
return 0;
}
Check if a given string is a palindrome.
#include
#include
int main() {
std::string str, revStr;
std::cout << "Enter a string: ";
std::cin >> str;
revStr = std::string(str.rbegin(), str.rend());
if (str == revStr) {
std::cout << str << " is a palindrome." << std::endl;
} else {
std::cout << str << " is not a palindrome." << std::endl;
}
return 0;
}
Count the number of vowels in a given string.
#include
#include
int main() {
std::string str;
int count = 0;
std::cout << "Enter a string: ";
std::cin >> str;
for (char ch : str) {
if (ch == 'a' || ch == 'e' || ch == 'i' || ch == 'o' || ch == 'u' ||
ch == 'A' || ch == 'E' || ch == 'I' || ch == 'O' || ch == 'U') {
++count;
}
}
std::cout << "Number of vowels in the string: " << count << std::endl;
return 0;
}
Demonstrate the basic use of pointers.
#include
int main() {
int var = 20;
int* ptr = &var;
std::cout << "Value of var: " << var << std::endl;
std::cout << "Address of var: " << &var << std::endl;
std::cout << "Value of ptr: " << ptr << std::endl;
std::cout << "Value pointed to by ptr: " << *ptr << std::endl;
return 0;
}
Allocate memory dynamically for an array.
#include
int main() {
int n;
std::cout << "Enter the number of elements: ";
std::cin >> n;
int* arr = new int[n];
std::cout << "Enter the elements of the array: ";
for (int i = 0; i < n; ++i) {
std::cin >> arr[i];
}
std::cout << "Array elements: ";
for (int i = 0; i < n; ++i) {
std::cout << arr[i] << " ";
}
std::cout << std::endl;
delete[] arr;
return 0;
}
Swap two numbers using pointers.
#include
void swap(int* a, int* b) {
int temp = *a;
*a = *b;
*b = temp;
}
int main() {
int x, y;
std::cout << "Enter two numbers: ";
std::cin >> x >> y;
std::cout << "Before swapping: x = " << x << ", y = " << y << std::endl;
swap(&x, &y);
std::cout << "After swapping: x = " << x << ", y = " << y << std::endl;
return 0;
}
Reverse a string using pointers.
#include
#include
void reverse(char* str) {
int n = strlen(str);
for (int i = 0; i < n / 2; ++i) {
char temp = str[i];
str[i] = str[n - i - 1];
str[n - i - 1] = temp;
}
}
int main() {
char str[100];
std::cout << "Enter a string: ";
std::cin >> str;
reverse(str);
std::cout << "Reversed string: " << str << std::endl;
return 0;
}
Create a dynamic 2D array.
#include
int main() {
int rows, cols;
std::cout << "Enter number of rows and columns: ";
std::cin >> rows >> cols;
int** arr = new int*[rows];
for (int i = 0; i < rows; ++i) {
arr[i] = new int[cols];
}
std::cout << "Enter elements of the array:" << std::endl;
for (int i = 0; i < rows; ++i) {
for (int j = 0; j < cols; ++j) {
std::cin >> arr[i][j];
}
}
std::cout << "Array elements:" << std::endl;
for (int i = 0; i < rows; ++i) {
for (int j = 0; j < cols; ++j) {
std::cout << arr[i][j] << " ";
}
std::cout << std::endl;
}
for (int i = 0; i < rows; ++i) {
delete[] arr[i];
}
delete[] arr;
return 0;
}
Create a structure for a student and display the details.
#include
#include
struct Student {
std::string name;
int roll;
float marks;
};
int main() {
Student s1;
std::cout << "Enter name: ";
std::cin >> s1.name;
std::cout << "Enter roll number: ";
std::cin >> s1.roll;
std::cout << "Enter marks: ";
std::cin >> s1.marks;
std::cout << "Student Details:" << std::endl;
std::cout << "Name: " << s1.name << std::endl;
std::cout << "Roll Number: " << s1.roll << std::endl;
std::cout << "Marks: " << s1.marks << std::endl;
return 0;
}
Create a structure for an employee and display the details.
#include
#include
struct Employee {
std::string name;
int id;
float salary;
};
int main() {
Employee e1;
std::cout << "Enter name: ";
std::cin >> e1.name;
std::cout << "Enter ID: ";
std::cin >> e1.id;
std::cout << "Enter salary: ";
std::cin >> e1.salary;
std::cout << "Employee Details:" << std::endl;
std::cout << "Name: " << e1.name << std::endl;
std::cout << "ID: " << e1.id << std::endl;
std::cout << "Salary: " << e1.salary << std::endl;
return 0;
}
Read from and write to a file.
#include
#include
#include
int main() {
std::ofstream outFile("example.txt");
outFile << "Hello, file!" << std::endl;
outFile.close();
std::ifstream inFile("example.txt");
std::string content;
std::getline(inFile, content);
std::cout << "Content of file: " << content << std::endl;
inFile.close();
return 0;
}
Write an array of integers to a file.
#include
#include
int main() {
int n;
std::cout << "Enter the number of elements: ";
std::cin >> n;
int arr[n];
std::cout << "Enter the elements of the array: ";
for (int i = 0; i < n; ++i) {
std::cin >> arr[i];
}
std::ofstream outFile("array.txt");
for (int i = 0; i < n; ++i) {
outFile << arr[i] << " ";
}
outFile.close();
std::ifstream inFile("array.txt");
int num;
std::cout << "Content of file: ";
while (inFile >> num) {
std::cout << num << " ";
}
std::cout << std::endl;
inFile.close();
return 0;
}
Read student data from a file and display it.
#include
#include
#include
struct Student {
std::string name;
int roll;
float marks;
};
int main() {
Student s;
std::ifstream inFile("student.txt");
if (inFile.is_open()) {
while (inFile >> s.name >> s.roll >> s.marks) {
std::cout << "Name: " << s.name << ", Roll: " << s.roll << ", Marks: " << s.marks << std::endl;
}
inFile.close();
} else {
std::cout << "Unable to open file." << std::endl;
}
return 0;
}
Create a class for a Rectangle with attributes length and width, and methods to calculate the area and perimeter.
#include
class Rectangle {
private:
double length;
double width;
public:
void setDimensions(double l, double w) {
length = l;
width = w;
}
double getArea() {
return length * width;
}
double getPerimeter() {
return 2 * (length + width);
}
};
int main() {
Rectangle rect;
rect.setDimensions(5.0, 3.0);
std::cout << "Area: " << rect.getArea() << std::endl;
std::cout << "Perimeter: " << rect.getPerimeter() << std::endl;
return 0;
}
Create a base class Shape and derive classes Circle and Square with appropriate attributes and methods.
#include
#include
class Shape {
public:
virtual double getArea() = 0;
virtual double getPerimeter() = 0;
};
class Circle : public Shape {
private:
double radius;
public:
Circle(double r) : radius(r) {}
double getArea() override {
return M_PI * radius * radius;
}
double getPerimeter() override {
return 2 * M_PI * radius;
}
};
class Square : public Shape {
private:
double side;
public:
Square(double s) : side(s) {}
double getArea() override {
return side * side;
}
double getPerimeter() override {
return 4 * side;
}
};
int main() {
Circle c(3.0);
Square s(4.0);
std::cout << "Circle Area: " << c.getArea() << std::endl;
std::cout << "Circle Perimeter: " << c.getPerimeter() << std::endl;
std::cout << "Square Area: " << s.getArea() << std::endl;
std::cout << "Square Perimeter: " << s.getPerimeter() << std::endl;
return 0;
}
Create a class hierarchy with polymorphic behavior for different types of employees: FullTimeEmployee and PartTimeEmployee.
#include
class Employee {
public:
virtual void displayInfo() = 0;
virtual double calculateSalary() = 0;
};
class FullTimeEmployee : public Employee {
private:
std::string name;
double salary;
public:
FullTimeEmployee(std::string n, double s) : name(n), salary(s) {}
void displayInfo() override {
std::cout << "Full-Time Employee: " << name << std::endl;
}
double calculateSalary() override {
return salary;
}
};
class PartTimeEmployee : public Employee {
private:
std::string name;
double hourlyRate;
int hoursWorked;
public:
PartTimeEmployee(std::string n, double rate, int hours) : name(n), hourlyRate(rate), hoursWorked(hours) {}
void displayInfo() override {
std::cout << "Part-Time Employee: " << name << std::endl;
}
double calculateSalary() override {
return hourlyRate * hoursWorked;
}
};
int main() {
FullTimeEmployee fte("John Doe", 5000.0);
PartTimeEmployee pte("Jane Smith", 20.0, 100);
fte.displayInfo();
std::cout << "Salary: $" << fte.calculateSalary() << std::endl;
pte.displayInfo();
std::cout << "Salary: $" << pte.calculateSalary() << std::endl;
return 0;
}
Create a program that demonstrates basic exception handling with try-catch blocks.
#include
int main() {
int a, b;
std::cout << "Enter two integers: ";
std::cin >> a >> b;
try {
if (b == 0) {
throw std::runtime_error("Division by zero error.");
}
std::cout << "Result: " << a / b << std::endl;
} catch (const std::exception& e) {
std::cout << "Exception: " << e.what() << std::endl;
}
return 0;
}
Create a program that handles multiple exceptions.
#include
#include
double divide(int a, int b) {
if (b == 0) {
throw std::runtime_error("Division by zero error.");
}
return static_cast(a) / b;
}
int main() {
int a, b;
std::cout << "Enter two integers: ";
std::cin >> a >> b;
try {
std::cout << "Result: " << divide(a, b) << std::endl;
} catch (const std::runtime_error& e) {
std::cout << "Runtime Error: " << e.what() << std::endl;
} catch (const std::exception& e) {
std::cout << "Exception: " << e.what() << std::endl;
}
return 0;
}
Create a custom exception class and use it in a program.
#include
#include
class CustomException : public std::runtime_error {
public:
CustomException(const std::string& message) : std::runtime_error(message) {}
};
double divide(int a, int b) {
if (b == 0) {
throw CustomException("Custom Exception: Division by zero.");
}
return static_cast(a) / b;
}
int main() {
int a, b;
std::cout << "Enter two integers: ";
std::cin >> a >> b;
try {
std::cout << "Result: " << divide(a, b) << std::endl;
} catch (const CustomException& e) {
std::cout << "Custom Exception: " << e.what() << std::endl;
} catch (const std::exception& e) {
std::cout << "Exception: " << e.what() << std::endl;
}
return 0;
}
Demonstrate the use of vectors in C++.
#include
#include
int main() {
std::vector vec;
// Add elements to vector
vec.push_back(10);
vec.push_back(20);
vec.push_back(30);
// Display elements
std::cout << "Vector elements: ";
for (int i : vec) {
std::cout << i << " ";
}
std::cout << std::endl;
// Remove last element
vec.pop_back();
// Display elements after pop_back
std::cout << "Vector elements after pop_back: ";
for (int i : vec) {
std::cout << i << " ";
}
std::cout << std::endl;
return 0;
}
Demonstrate the use of maps in C++.
#include
#include
Demonstrate the use of sets in C++.
#include
#include
int main() {
std::set numSet;
// Insert elements
numSet.insert(10);
numSet.insert(20);
numSet.insert(30);
numSet.insert(20); // Duplicate element
// Display elements
std::cout << "Set elements: ";
for (int i : numSet) {
std::cout << i << " ";
}
std::cout << std::endl;
// Check if an element exists
int num = 20;
if (numSet.find(num) != numSet.end()) {
std::cout << num << " is in the set." << std::endl;
} else {
std::cout << num <<