import java.util.Scanner;

public class Calculator {
    
    public static void main(String args[]){
        Scanner sc = new Scanner(System.in);
        char ch = 'y',f;
        do{
            System.out.println("Enter the first number: ");
            float a = sc.nextFloat();

            System.out.println("Enter the operator (+,-,/,*): ");
            char b = sc.next().charAt(0);

            if((b != '+') && (b != '-') && (b != '/') && (b != '*') && (b != 'x')){
                System.out.println("Invalid operator.");
            }

            System.out.println("Enter the second number: ");
            float c = sc.nextFloat();

            switch(b){
                case '+': 
                    float d = a+c;
                    System.out.println(+a+" + "+c+" = "+d);
                    break;
                case '-': 
                    float e = a-c;
                    System.out.println(+a+" - "+c+" = "+e);
                    break;
                case '/': 
                    float g = a / c;
                    System.out.println(+a+" / "+c+" = "+g);
                    break;
                case 'x':
                case '*': 
                    float h = a*c;
                    System.out.println(+a+" * "+c+" = "+h);
                    break;
            }
            
            System.out.println("Do you want to perform another calculation (y/n)?");
            f = sc.next().charAt(0);
        } while(f == ch);

    }
}