Colm wise web Print(all test cases shows error but code)

#1

package TwoDArrays;

import java.util.Scanner;

public class WavePrintColmnWise {

public static void main(String[] args) {
	//int[][] arr=takeInput();
//	int[][] array= {{11,12,13,14},{21,22,23,24},{31,32,33,34},{41,42,43,44}};
	
	


	Scanner s=new Scanner(System.in);
	System.out.println("Enter the no of rows ");
	int rows=s.nextInt();
	int arr[][]= new int [rows][];
	for(int row=0;row<rows;row++)
	{
		
		int cols=s.nextInt()

;
arr[row]=new int[cols];
for(int col=0;col<cols;col++){

			arr[row][col]=s.nextInt();
			
		}
		}
	
	
		for(int j=0;j<arr.length;j++)
		{
				if(j%2==0)
					
				{
					for(int i=0;i<arr.length;i++)
					{
						System.out.print(arr[i][j]+" ");
					}
					
				}
				else
				{
					for(int i=arr.length-1;i>=0;i--)
					{
						System.out.print(arr[i][j]+" ");
					}
					
					
				}
			
		}
		System.out.print("End");
		
		}

}

#2

Which problem is this?
You have marked it in double sided arrow

#3

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