A calculator with operations add, subtract, multiplication and division.

int add(int a, int b)
{
  return a + b;
}

int subtract(int a, int b)
{
  return a - b;
}

int multiply(int a, int b)
{
  return a * b;
}

int divide(int a, int b)
{
  return a / b;
}

int main()
{
  int a, b;
  char operation;
  
  cout << "Enter first number: ";
  cin >> a;
  cout << "Enter second number: ";
  cin >> b;
  
  cout << "Enter an operation: +, -, * or / ";
  cin >> operation;
  cout << endl;
  
  switch (operation) {
    case '+':
      cout << "The result is " << add(a, b) << endl;
      break;
    case '-':
      cout << "The result is " << subtract(a, b) << endl;
      break;