Java comparing 10<-5 gets true

Question

i'm learning java and got a problem, I have an max/min exercise and tried the code bellow, for positive numbers it work fine, but when i try negative numbers the things got messy.

If you enter 5 you get min = 5 and max = 5, if you enter 10 after, you get min = 5 max = 10, so far so good, but if you type -5, you get min = -5 and max = -5, and things still get weirder, if you type 7, you get min =-5 and max = 7.

Can someone explain why this happens?

public static void main(String[] args) {
    int ctrl;
    int min = 0;
    int max = 0;
    boolean hasNextInt;
    Scanner scanner = new Scanner(System.in);
    int counter = 0;
    while (true) {
        System.out.println("Enter your number:");
        hasNextInt = scanner.hasNextInt();  
        if(hasNextInt) {
            ctrl = scanner.nextInt();
            if(counter == 0) {
                min = ctrl;
                max = ctrl;
                counter ++;
            }
            if(min>ctrl)
                min = ctrl;
            if(max<ctrl);
                max = ctrl;
            System.out.println("Minimum Number entered: " + min);
            System.out.println("Maximum Number entered: " + max);
            System.out.println("");
            scanner.nextLine();
        }else {
            System.out.println("Invalid Number. Program stop working.");
            break;
        }
    }
    scanner.close();
}

Duplicate: https://stackoverflow.com/questions/14112515/semicolon-at-end-of-if-statement — Tom, Feb 18 '19 at 13:03

Thilo · Accepted Answer · 2019-02-18T23:26:26.070

4

if(max<ctrl);
  max = ctrl;

That indentation is highly misleading.

Use an IDE that does code formatting. What you really wrote is

if(max<ctrl){}
max = ctrl;

Also avoid if/else/for etc without {}.

edited Feb 18 '19 at 23:26

answered Feb 18 '19 at 13:03

Thilo

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Java comparing 10<-5 gets true

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