Calculator Program in C++

Program to make basic calculator

This can be done by simply using the switch case where the cases will be the operators (+,-,*,/).

Algorithm

1. Prompt the user to enter two operands on which to perform the operation.
2. Prompt the user to enter the operator to use.
3. Use a switch statement to check if the operator matches any of the cases ('+', '-', '*', '/'). If the operator does not match any of these cases, display an error message.
4. If the operator does match one of the cases, perform the corresponding operation on the operands and print the result.

Code

// C++ program to create calculator
#include <iostream>
using namespace std;

// Main program
int main() {
    char oper;
    float a, b;

    // It allow user to enter the operands
    cout << "Enter two operands: ";
    cin >> a >> b;

    // It allows user to enter operator i.e. +, -, *, /
    cout << "Enter operator: ";
    cin >> oper;

    // Switch statement begins
    switch (oper) {
        // If operator is '+'
        case '+':
            cout << a + b;
            break;
        // If operator is '-'
        case '-':
            cout << a - b;
            break;
        // If operator is '*'
        case '*':
            cout << a * b;
            break;
        // If operator is '/'
        case '/':
            cout << a / b;
            break;
        // If any other operator display error message
        default:
            cout << "Error! Incorrect operator";
            break;
    }
    return 0;
}

Output

Input:
Enter two operands: 10 20
Enter operator: *

Output:
200