poj 1870 java

import java.util.Scanner;

public class POJ_1870 {

	
	public static void main(String[] args) {
		
		Scanner scan = new Scanner(System.in);
		
		while(true){
			int a = scan.nextInt();
			int b = scan.nextInt();
			if(a==0&&b==0)
				break;
			A3 p = new A3(0,0);
			p = cal(a);
			A3 p1 = new A3(p.x,p.y);
			p = cal(b);
			A3 p2 = new A3(p.x,p.y);
			int x = p1.x-p2.x;
			int y = p1.y-p2.y;
			int ans;
			if(x*y<=0)
				ans = Math.max(Math.abs(x), Math.abs(y));
			else
				ans = Math.abs(x+y);
			System.out.printf("The distance between cells %d and %d is %d.",a,b,ans);
			System.out.println();
		}

	}

	public static A3 cal(int a) {
		if(a == 1){
			return new A3(0,0);
		}
		int x;
		int y;
		int n = 0;
		while(3*(n-1)*n+1<a)     // 3*(n-1)*n+1  為第n圈最後一個數
			n++;
		n--;
		a -= 3*(n-1)*n+1;
		
		if(a<=n){               // 詳細注釋見我的   poj 2265
			x = n;
			y = -a;
		}else if(a>n&&a<=2*n){
			x = 2*n-a;
			y = -n;
		}else if(a>2*n&&a<=3*n){
			x = 2*n-a;
			y = -n-x;
		}else if(a>3*n&&a<=4*n){
			x = -n;
			y = a-3*n;
		}else if(a>4*n&&a<=5*n){
			x = a-5*n;
			y = n;
		}else{
			x = a-5*n;
			y = n-x;
		}
		A3 p = new A3(x,y);
		return p;
	}

}

class A3{
	int x;
	int y;
	public A3(int x, int y) {
		super();
		this.x = x;
		this.y = y;
	}
	
}