Question

How do you make a calculator

Answer 1

#include <stdio.h>

int main() {
    char operator;
    double num1, num2, result;

    // Step 1: Request the mathematical operator from the user
    printf("Enter an operator (+, -, *, /): ");
    scanf("%c", &operator);

    // Step 2: Request the two numeric operands
    printf("Enter two numbers: ");
    scanf("%lf %lf", &num1, &num2);

    // Step 3: Evaluate the operator and compute the result
    switch (operator) {
        case '+':
            result = num1 + num2;
            printf("%.2lf + %.2lf = %.2lf\n", num1, num2, result);
            break;

        case '-':
            result = num1 - num2;
            printf("%.2lf - %.2lf = %.2lf\n", num1, num2, result);
            break;

        case '*':
            result = num1 * num2;
            printf("%.2lf * %.2lf = %.2lf\n", num1, num2, result);
            break;

        case '/':
            // Edge case validation: avoid division by zero
            if (num2 != 0.0) {
                result = num1 / num2;
                printf("%.2lf / %.2lf = %.2lf\n", num1, num2, result);
            } else {
                printf("Error! Division by zero is not allowed.\n");
            }
            break;

        // Triggers if the user types an invalid math symbol
        default:
            printf("Error! Invalid operator entered.\n");
    }

    return 0;
}

Answer 2

print("| Welcome to the second edition of the calculator |\n")
#in phathon

Num1 = float(input("First number :"))
Oper = input("Choose one of the operations ' +, -, *, /, % ':")
Num2 = float(input("second number :"))
if Oper == '+' :
    Result = Num1 + Num2
    print(Num1,'+',Num2,'= ',Result)
    
elif Oper == '-' :
    Result = Num1 - Num2
    print(Num1,'-',Num2,'= ',Result)
    
elif Oper == '*' :
    Result = Num1 * Num2
    print(Num1,'*',Num2,'= ',Result)
    
elif Oper == '/' :
    Result = Num1 / Num2
    print(Num1,'/',Num2,'= ',Result)
    
elif Oper == '%' :
    Result = Num1 % Num2
    print(Num1,'%',Num2,'= ',Result)