Pair Class

jsumabat posted on Nov. 21, 2019, 4:07 p.m.

public class Main {
    static class Pair implements Comparable<Pair>{
        // fields
        int x;
        int y;
        // constructor
        Pair (int a, int b){
            x = a;
            y = b;
        }

        // Arrays.sort() calls compareTo, we are telling Java how to sort Pair
        public int compareTo(Pair o) {
            return x-o.x;
        }
    }

    public static void main(String[] args) {
        Pair p1 = new Pair(5, 4);
        Pair arr[] = new Pair[5];
        // assume i input it already
        Arrays.sort(arr);
    }
}

Comments

3

wleungBVG commented on March 8, 2020, 10:34 p.m.

Using subtraction in the compareTo function is dangerous as it can result in integer overflow/underflow. It is best to determine whether to return -1, 0, or -1 using if statements rather than subtraction.

0

Encodeous commented on March 12, 2020, 7:42 a.m.

Or in this case, you can use Integer.compare for the x values.
2

sankeeth_ganeswaran commented on March 9, 2020, 6:07 p.m.

thanks dude