queen_check

import java.util.Arrays;
import java.util.Scanner;
class Set{
    int[] row, col, diag1, diag2;
    int row_t, col_t, diag1_t, diag2_t, size;
    Set(int n)
    {
        row = new int[n];
        col = new int[n];
        diag1 = new int[n];
        diag2 = new int[n];
        size = n;
        Arrays.fill(diag1, -n);
        Arrays.fill(diag2, -n);
        Arrays.fill(row, -n);
        Arrays.fill(col, -n);
        row_t = col_t = diag1_t = diag2_t = -1;
    }

    boolean isPresent(int[] arr, int n)
    {
        for(int i = 0; i < size; i++)
        {
            if(arr[i] == n)
                return true;
        }
        return false;
    }

    void rowAdd(int n)
    {
        if(!isPresent(row, n))
            row[++row_t] = n;
    }

    void colAdd(int n)
    {
        if(!isPresent(col, n))
            col[++col_t] = n;
    }

    void diag1Add(int n)
    {
        if(!isPresent(diag1, n))
            diag1[++diag1_t] = n;
    }

    void diag2Add(int n)
    {
        if(!isPresent(diag2, n))
            diag2[++diag2_t] = n;
    }

    boolean result()
    {
        if(row_t == col_t && row_t == diag1_t && row_t == diag2_t)
            return true;
        return false;
    }

}

public class queen_check {
    public static void main(String Args[])
    {
        Scanner sc = new Scanner(System.in);
        System.out.print("Enter no. of rows or columns : ");
        int size  = sc.nextInt();
        int[][] board = new int[size][size];
        Set s = new Set(size);

        for(int i = 0; i < size; i++)
        {
            System.out.print("\n\nEnter queen "+ (i+1) + " row : ");
            int r = sc.nextInt();
            System.out.print("Enter queen "+ (i+1) + " column : ");
            int c = sc.nextInt();
            board[r][c] = 1;
        }
        System.out.println("\n");
        for(int i = 0; i < size; i++)
        {
            for(int j = 0; j < size; j++)
            {
                if(board[i][j] == 1)
                    System.out.print("Q\t");
                else
                    System.out.print(".\t");
            }
            System.out.println("\n");
        }

        for(int i = 0; i < size; i++)
        {
            for(int j = 0; j < size; j++)
            {
                if(board[i][j] == 1)
                {
                    s.rowAdd(i);
                    s.colAdd(j);
                    s.diag1Add(i-j);
                    s.diag2Add(i+j);
                }
            }
        }

        System.out.print("\n\n r c d1 d2 : "+s.row_t+" "+s.col_t+" "+s.diag1_t+" "+s.diag2_t);

        if(s.result())
            System.out.println("\n\nSUCCESS!!!");
        else
            System.out.println("\n\nFail!");

    }
}