Method convert

java/0051-n-queens.java:110–120

(int n, int col)

    }

    private String convert(int n, int col) {
        StringBuilder res = new StringBuilder();
        for (int i = 0; i < n; i++) {
            if (i == col) {
                res.append("Q");
            } else {
                res.append(".");
            }
        }
        return res.toString();
    }
}