第一题没思路，第二题差十分钟写出下面代码，后面的没看，我哭了

import java.util.LinkedList; import java.util.Scanner; import java.util.Stack; public class Main { public static void main(String[] args) { Scanner in = new Scanner(System.in); LinkedList<StringBuilder> list = new LinkedList<>(); while (in.hasNextLine()) { StringBuilder sb = new StringBuilder(in.next()); //            list.add(sb);  f(sb);
        }

    } public static void f(StringBuilder sb){ StringBuilder res = new StringBuilder(); int len = sb.length(); //            System.out.println(sb.toString());  Stack<Character> stack = new Stack<>(); int j = 0; if (sb.charAt(0)=='-') { stack.push('('); stack.push('$');
            j=1;
        }else { stack.push('$');
        } for (int i = j; i < len; i++) { if (sb.charAt(i)=='.'){
                len =len>i+3? i+3:len;
            } stack.push(sb.charAt(i));
        } int count = 0; if (sb.charAt(0)=='-'){
            res.append(")");
        } while (!stack.empty()){
            res.append(stack.pop()); if (!stack.empty()&&stack.peek()=='.'){
                res.append(stack.pop()); while (stack.peek()!='$'){ if (stack.peek()!='$')res.append(stack.pop()); else break; if (stack.peek()!='$')res.append(stack.pop()); else break; if (stack.peek()!='$')res.append(stack.pop()); else break; if (stack.peek()!='$') res.append(","); else break;
                }
            }
        }
        res = res.reverse(); System.out.println(res);
    }

}