package com.company;

import org.junit.Test;

import java.util.ArrayList;
import java.util.Collections;

/**
 * Created by rajan on 21-01-2017.
 **/
public class SpiralMatrixTraversal {
    public static void main(String[] args) {
        int[][] arr={
                {1,2,3},
                {7,8,9}
        };

        int[][] arr2={{1}};
        ArrayList<Integer> ans= findSpiral(arr);
        for(int i: ans)
        {
            System.out.println(i);
        }
    }

    public static void TraverseList(ListNode head)
    {
        if(head==null) return;
        ListNode temp=head;
        while(temp!=null) {
            System.out.println(temp.data);
            temp = temp.next;
        }
    }

    public static ArrayList<Integer> findSpiral(int[][] arr) {

        ArrayList<Integer> ans =new ArrayList<>();

        int row_min=0;
        int col_min=0;

        int row_max =arr.length -1;            //Number of rows
        int col_max =arr[0].length -1;         //number of columns

        int row_pos=0;
        int col_pos=0;

        while(row_min<=row_max && col_min<=col_max)
        {
            if(row_pos==row_min && col_pos==col_min)            //Upper left
            {
                while(col_pos<=col_max)
                {
                    ans.add(arr[row_pos][col_pos]);
                    col_pos+=1;
                }
                col_pos-=1;

                row_pos+=1;
                row_min+=1;
            }
            else if(row_pos==row_max && col_pos==col_max)        //Lower Right
            {
                while(col_pos>=col_min)
                {
                    ans.add(arr[row_pos][col_pos]);
                    col_pos-=1;
                }
                col_pos+=1;
                row_pos-=1;
                row_max-=1;
            }
            else if(row_pos==row_min && col_pos==col_max)        //Upper right
            {
                while(row_pos<=row_max)
                {
                    ans.add(arr[row_pos][col_pos]);
                    row_pos+=1;
                }
                row_pos-=1;
                col_pos-=1;
                col_max-=1;
            }
            else if(row_pos==row_max && col_pos==col_min)        //Lower left
            {
                while(row_pos>=row_min)
                {
                    ans.add(arr[row_pos][col_pos]);

                    row_pos-=1;
                }
                row_pos+=1;
                col_pos+=1;
                col_min+=1;
            }
        }
        return ans;
    }

    @Test
    public void test1()
    {
        int[][] arr={{1}};
        ArrayList<Integer>al=new ArrayList<>();
        Integer[] ans={1};
        Collections.addAll(al,ans);

        org.junit.Assert.assertEquals(al,findSpiral(arr));
    }

    @Test
    public void test2()
    {
        int[][] arr={
                {1,2},
                {4,5},
        };
        ArrayList<Integer>al=new ArrayList<>();
        Integer[] ans={1,2,5,4};
        Collections.addAll(al,ans);

        org.junit.Assert.assertEquals(al,findSpiral(arr));
    }

    @Test
    public void test3()
    {
        int[][] arr={
                {1,2,3},
                {4,5,6},
                {7,8,9}
        };
        ArrayList<Integer>al=new ArrayList<>();
        Integer[] ans={1,2,3,6,9,8,7,4,5};
        Collections.addAll(al,ans);

        org.junit.Assert.assertEquals(al,findSpiral(arr));
    }

}