How to make Simple Calculator in C

// Performs addition, subtraction, multiplication or division depending the input from user build by Zahid Wadiwale
# include <stdio.h>
#include<windows.h>
int main() {
    SetConsoleTitle("Calculator Project - by Zahid Wadiwale");
    char operator;
    double firstNumber,secondNumber;
    printf(" Zahid Calculator in C \n Enter an operator (+, -, *,/,): ");
    scanf("%c", &operator);
    printf("Enter two operands: ");
    scanf("%lf %lf",&firstNumber, &secondNumber);
    switch(operator)
    {
        case '+':
            printf("%.1lf + %.1lf = %.1lf",firstNumber, secondNumber, firstNumber + secondNumber);
            break;
        case '-':
            printf("%.1lf - %.1lf = %.1lf",firstNumber, secondNumber, firstNumber - secondNumber);
            break;
        case '*':
            printf("%.1lf * %.1lf = %.1lf",firstNumber, secondNumber, firstNumber * secondNumber);
            break;
        case '/':
            printf("%.1lf / %.1lf = %.1lf",firstNumber, secondNumber, firstNumber / secondNumber);
            break;
        // operator doesn't match any case constant (+, -, *, /)
        default:
            printf("Zahid calculator \n Error! operator is not correct \n");
    }
    return 0;
}