C program to create calculator using switch case

A calculator is an essential device and it makes the calculations easier and faster. In this blog post, you will learn to create a simple calculator in C programming using the switch statement.

The blog post covers the following questions related to the simple calculator program:

How do you make a calculator app using C?
Can we make a calculator using the C language?
How do you make a calculator code?
How shall I start the calculator program?
How do I create a calculator using the C language?
How does a simple calculator work?

You should have basic knowledge of the following topics to understand the calculator code.

Working Of Simple Calculator Using switch-case:

This is a simple C program to create a calculator using the switch case. The below C code asks the user to enter two numbers and an arithmetic operator +, -, *, /. The switch case also validates the validity of the arithmetic operator and displays a warning message.

Here I am breaking the working behavior of the simple C program calculator in the following steps. It helps you to understand the flow of the simple calculator code.

Enter the first number then the arithmetic operator [ + , - , * , / ] and in the last second number.
The switch case checks the validity of the arithmetic operator like if the user enters another character in place of the +,-, * or/, it will give the warning message “Please Enter Valid Operator”.
If the user enters the valid operator, the switch case performs the calculation on the basis of the operator.
The last printf is used to print the result of the calculation in a meaningful format.

#include <stdio.h>

int main()
{
    char choice;
    float number1, number2,result;
    char flag = 1;


    printf("SIMPLE STANDARD CALCULATOR\n\n");
    printf("Please follow below format for calculation\n\n");
    printf("Number1   [+ - * /]  Number2\n");

    /* Input two number and operator from user */
    scanf("%f %c %f", &number1, &choice, &number2);


    // Switch case perform calculation on the basis of operator
    switch(choice)
    {
    case '+':
        result = number1 + number2;
        break;

    case '-':
        result = number1 - number2;
        break;

    case '*':
        result = number1 * number2;
        break;

    case '/':
        result = number1 / number2;
        break;

    default:
        flag = 0;
        break;
    }

    // Prints the result
    if(flag)
    {
        printf("%.2f %c %.2f = %.2f\n\n", number1, choice, number2, result);
    }
    else
    {
        printf("Please Enter Valid Operator\n\n");
    }

    return 0;
}

Output 1:

When the user enters 12, + (arithmetic operator), and 25.