Java – how to select a value from an array?

How do I select a value from an array? For example, string [] ans = {'', "– ''," / "," * "}; Then I want to choose ""

public static void main(String[] args) {
    String[] ans = {"+","-","/","*"};
    Random random = new Random();
    Scanner calcu = new Scanner(system.in);
    System.out.print("Enter First number: ");
    numOne = calcu.nextInt();
    System.out.print("Enter Second number: ");
    numTwo = calcu.nextInt();
    System.out.print("Choose an Operator to use");

}

Solution

You can use ans [0] for "" and so on

ans[0] = "+";
ans[1] = "-";
ans[2] = "/";
ans[3] ="*";

In your case, this code will help you:

public static void main(String[] a) {

        String[] ans = {"+","*"};
        double result = 0;
        Scanner calcu = new Scanner(system.in);
        System.out.print("Enter First number: ");
        int numOne = calcu.nextInt();
        System.out.print("Enter Second number: ");
        int numTwo = calcu.nextInt();
        System.out.print("Choose an Operator to use");
        String oparation= calcu.next();

        if(oparation.equals(ans[0])){
           result = numOne + numTwo;
        }
        else if(oparation.equals(ans[1])){
            result = numOne - numTwo;
        }
        else if(oparation.equals(ans[2])){
            result = numOne / numTwo;

        } else if(oparation.equals(ans[3])){
            result = numOne * numTwo;
        }
        System.out.println("result is " + result);

   }

If you want to use the switch statement to get the same result:

public static void main(String[] a) {

        double result = 0;
        Scanner calcu = new Scanner(system.in);
        System.out.print("Enter First number: ");
        int numOne = calcu.nextInt();
        System.out.print("Enter Second number: ");
        int numTwo = calcu.nextInt();
        System.out.print("Choose an Operator to use");
        String oparation= calcu.next();

        switch(oparation){
            case "+" :
            result = numOne + numTwo;
            break;

            case "-" :
            result = numOne - numTwo;
            break;

            case "/" :
            result = numOne / numTwo;
            break;

            case "*" :
            result = numOne * numTwo;
            break;
        }
        System.out.println("result is " + result);

   }

However, using the switch statement, if you want to compare variables such as case ans [0]: instead of case "*", you can use enum