codeforces 567A Lineland Mail program in java

LinelandMail.java

import java.util.Scanner;

public class LinelandMail
{
    static int sub(int a,int b){
        if(a >= 0 && b >= 0){
            return Math.abs(a-b);
        }else if(a <= 0 && b <= 0){
            return Math.abs((a*-1)-(b*-1));
        }else if(a >= 0 && b <= 0){
            return Math.abs(a+(b*-1));
        }else if(b >= 0 && a <= 0){
            return Math.abs(b+(a*-1));
        }else
            return 0;
    }
    static int getMinMax(int i,int j,int n,int[] ip,int[] op){
        if(i == 0){
            op[j] = LinelandMail.sub(ip[0], ip[1]);
            op[++j] = LinelandMail.sub(ip[0], ip[n-1]);
        }else if(i == n-1){
            op[++j] = LinelandMail.sub(ip[n-1], ip[n-2]);
            op[++j] = LinelandMail.sub(ip[n-1], ip[0]);
        }else{
            int mina = LinelandMail.sub(ip[i], ip[i+1]);
            int minb = LinelandMail.sub(ip[i], ip[i-1]);
            int minc = LinelandMail.sub(ip[i], ip[0]);
            int mind = LinelandMail.sub(ip[i], ip[n-1]);
            op[++j] = Math.min(mina, minb);
            op[++j] = Math.max(minc, mind);
        }
        return j;
    }
    public static void main(String[] args)
    {
        Scanner z = new Scanner(System.in);
        int n = z.nextInt();
        int[] ip = new int[n];
        int[] op = new int[n*2];
        for(int i=0;i<n;i++)
            ip[i] = z.nextInt();
        int j=0;
        for(int i=0;i<n;i++){
            if(ip[i] < 0){
                j = LinelandMail.getMinMax(i, j, n, ip, op);
            }else{
                j = LinelandMail.getMinMax(i, j, n, ip, op);
            }
        }
        for(int i=0;i<n*2-1;i+=2)
            System.out.println(op[i]+" "+op[i+1]);
        z.close();
    }
}