NQueen Problem Solver in Java

NQueen.java

import java.util.*;
import java.awt.Point;
public class NQueen {
        public static final String ANSI_GREEN = "\u001B[32m";
        public static final String ANSI_RESET = "\u001B[0m";
        public static final String ANSI_WHITE = "\u001B[37m";
        private final int N;
        private final Set<Point> queens;
        public NQueen(int N) {
                this.N = N;
                this.queens = new HashSet<>();
        }
        private static int diff(int a, int b) {
                return Math.abs(a - b);
        }
        private static boolean canPut(Set<Point> queens, Point p) {
                if(queens.contains(p)) return false;
                for(var q:queens) {
                        if(q.x == p.x || q.y == p.y) return false;
                        if(diff(q.x, p.x) == diff(q.y, p.y)) {
                                return false;
                        }
                }
                return true;
        }
        private boolean tryPut(int n) {
                if(n == N) return true;
                for(int x = 0; x < N; x++) {
                        for(int y = 0; y < N; y++) {
                                var point = new Point(x, y);
                                if(canPut(queens, point)) {
                                        queens.add(point);
                                        var succeed = tryPut(n + 1);
                                        if(succeed) return true;
                                        queens.remove(point);
                                }
                        }
                }
                return false;
        }
        public void solve() {
                if(tryPut(0)) {
                        printBoard();
                }
        }
        private void printBoard() {
                for(int x = 0; x < N; x++) {
                        for(int y = 0; y < N; y++){
                                if(queens.contains(new Point(x, y))) {
                                        System.out.print(ANSI_GREEN + "Q " + ANSI_RESET);
                                } else {
                                        System.out.print(ANSI_WHITE + "X " + ANSI_RESET);
                                }
                        }
                        System.out.println();
                }
        }
        public static void main(String[] args) {
                var n = Integer.parseInt(args[0]);
                var nqueen = new NQueen(n);
                nqueen.solve();
        }
}