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Thread: Problem with condition

  1. #1
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    Default Problem with condition

    Hi, I'm having problem with this code.

    import java.io.*;
    public class ConditionalStatement {
        public static void main(String[]args) {
     
            BufferedReader input = new BufferedReader(new InputStreamReader(System.in));
     
            String num;
     
            try {
                num = input.readLine();
                int num1 = Integer.parseInt(num);
     
                int x=(num1>=0)? "positive":"negative";
                System.out.println("The number entered is "+x+".");
            }
     
            catch (IOException e) {
                System.out.println("Error!");
            }
     
            }
    }

    How come this line says "incompatible types"?
    int x=(num1>=0)? "positive":"negative";

    I just declared x as integer. What's wrong with that?


  2. #2
    Java kindergarten chronoz13's Avatar
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    Default Re: Problem with condition

    you are using ternary statement(operation), so i guess its a bit confusing.. ,,well the problem is this -- if num1 is greater than or equal to '0' then "ASSIGN" this String value to the variable 'x' which is an integer...


    change the variable 'x' to String
    Last edited by chronoz13; December 7th, 2009 at 04:21 AM.

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    Super Moderator Json's Avatar
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    Default Re: Problem with condition

    In the code you have.

    int x=(num1>=0)? "positive":"negative";

    You are trying to check the value of num1 and return a string and assign it to int x. Change the int x to be String x.

    // Json

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    shamed (December 7th, 2009)

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    Default Re: Problem with condition

    Thanks for answering, and thanks for the instruction. Now the problem is, it does not output the "negative" even if I input -1 or any negative number. It always displays "positive".

  7. #5
    Super Moderator Json's Avatar
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    Default Re: Problem with condition

    Rewrite it to be this.

    String x=(num1 >= 0 ? "positive" : "negative");

    I think your parenthesis was in the wrong place.

    // Json

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    shamed (December 7th, 2009)

  9. #6
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    Default Re: Problem with condition

    Quote Originally Posted by Json View Post
    Rewrite it to be this.

    String x=(num1 >= 0 ? "positive" : "negative");

    I think your parenthesis was in the wrong place.

    // Json
    Thanks for answering, and thanks for the instruction. Now the problem is, it does not output the "negative" even if I input -1 or any negative number. It always displays "positive".

  10. #7
    Super Moderator Json's Avatar
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    Default Re: Problem with condition

    This code works fine for me.

            int num1 = -1;
            String x = (num1 >= 0 ? "positive" : "negative");
            System.out.println(x);

    // Json

  11. #8
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    Default Re: Problem with condition

    Quote Originally Posted by Json View Post
    Rewrite it to be this.

    String x=(num1 >= 0 ? "positive" : "negative");

    I think your parenthesis was in the wrong place.

    // Json
    This code works fine with me. Thank you Json.