import java.util.*;
import java.io.*;
class GFG
{
static int R = 4, C = 4;
static void printSnake(int mat[][])
{
for(int i = 0; i < R; i++)
{
if(i % 2 == 0)
{
for(int j = 0; j < C; j++)
System.out.print(mat[i][j] + " ");
}
else
{
for(int j = C - 1; j >= 0; j--)
System.out.print(mat[i][j] + " ");
}
}
}
public static void main(String args[])
{
int arr[][] = {{1, 2, 3, 4},
{5, 6, 7, 8},
{9, 10, 11, 12},
{13, 14, 15, 16}};
printSnake(arr);
}
}
