public class Nknights
{
static int count =0;
public static void main(String[] args)
{
nKnights(new boolean[3][3], 0, 0, 0, 3, “”);
}
public static void nKnights(boolean[][] board, int row, int col, int kpsf, int tk, String ans)
{
if(kpsf==tk)
{
count++;
System.out.println(count+"."+ans);
return;
}
if(col==board[0].length)
{
row++;
col=0;
}
if(row==board.length)
{
return;
}
if(isitSafe(board, row, col))
{
board[row][col]=true;
nKnights(board, row, col+1, kpsf+1, tk, ans+row+col);
board[row][col]=false;
}
nKnights(board, row, col+1, kpsf, tk, ans);
}
public static boolean isitSafe(boolean[][] board, int row, int col)
{
int[] rowArr={-1,-2,-2,-1};
int[] colArr={2,1,-1,-2};
for(int i=0; i<4; i++)
{
int r=row=rowArr[i];
int c=col=colArr[i];
if(r>=0 && r<board.length &&c>=0&&c<board[0].length)
{
if(board[r][c])
{
return false;
}
}
}
return true;
}
}