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import java.text.DecimalFormat;
public class Main{
    static String formatNum(double s){
        // tùy chỉnh định dạng
        DecimalFormat dcf = new DecimalFormat("###,###.##");

        return dcf.format(s);
    }
    public static void main(String[] args) {
        System.out.println(formatNum(10000000000000000000000000000000002.2));
    }
}