import static choco.Choco.*;
import choco.cp.model.CPModel;
import choco.cp.solver.CPSolver;
import choco.kernel.model.Model;
import choco.cp.solver.search.integer.varselector.StaticVarOrder;
import choco.kernel.solver.Solver;
import choco.kernel.model.variables.integer.IntegerVariable;

public class NQueens3 {

    public static void main(String[] args) {

	int n = Integer.parseInt(args[0]);
	Model m = new CPModel();
	IntegerVariable [] q = makeIntVarArray("q",n,0,n-1); //new IntegerVariable[n];

	// columns constraint
       
	/*
	for (int i=0;i<n-1;i++)
	    for (int j=i+1;j<n;j++)
		m.addConstraint(neq(q[i],q[j]));
	*/
       

	m.addConstraint(allDifferent(q));

	// diagonal constraint
	for (int i=0;i<n-1;i++)
	    for (int j=i+1;j<n;j++)
		m.addConstraint(neq(Math.abs(i-j),abs(minus(q[i],q[j]))));

	Solver s = new CPSolver();
	s. read(m);

	//s.setVarIntSelector(new StaticVarOrder(s.getVar(q)));
	//s.setVarIntSelector(new VarOrder(s.getVar(q)));

	if (args[1].equals("first")){
	    System.out.println(s.solve(false));	
	    for (int i=0;i<n;i++){
		int x = s.getVar(q[i]).getVal();
		for (int j=0;j<x;j++) System.out.print("O");
		System.out.print("X");
		for (int j=x+1;j<n;j++) System.out.print("O");
		System.out.println();
		//System.out.println(s.getVar(q[i]));
	    }
	    s.printRuntimeSatistics();
	}
        if (args[1].equals("all")){
	    s.solve(true);
	    System.out.println("feasible: " +s.isFeasible());
	    System.out.println("nbSol: " + s.getNbSolutions());
	    s.printRuntimeSatistics();
	}
    }
}
//
// Now set up
// (1) column constraints
// (2) diagonal constraints
// (3) Alternative representation?
//