Problem:
Score : 200 points

Problem Statement

For a string S consisting of the uppercase English letters P and D, let the doctoral and postdoctoral quotient of S be the total number of occurrences of D and PD in S as contiguous substrings. For example, if S = PPDDP, it contains two occurrences of D and one occurrence of PD as contiguous substrings, so the doctoral and postdoctoral quotient of S is 3.

We have a string T consisting of P, D, and ?.

Among the strings that can be obtained by replacing each ? in T with P or D, find one with the maximum possible doctoral and postdoctoral quotient.

Constraints

1 \leq |T| \leq 2 \times 10^5

T consists of P, D, and ?.

Input

Input is given from Standard Input in the following format:

T

Output

Print one string with the maximum possible doctoral and postdoctoral quotient among the strings that can be obtained by replacing each ? in T with P or D.
If there are multiple such strings, you may print any of them.

Sample Input 1

PD?D??P

Sample Output 1

PDPDPDP

This string contains three occurrences of D and three occurrences of PD as contiguous substrings, so its doctoral and postdoctoral quotient is 6, which is the maximum doctoral and postdoctoral quotient of a string obtained by replacing each ? in T with P or D.

Sample Input 2

P?P?

Sample Output 2

PDPD

Solution in C# (.NET Core 3.1.201) (judge verdict: Accepted)

using System;
using System.Numerics;
using System.Linq;
using System.Collections.Generic;
using System.Text;
using System.Collections;

namespace debug
{
    class main
    {
        static void Main(string[] args)
        {
            //問題クラスを展開
            ProgramB a = new ProgramB();
            a.main();//実行する

        }

    }

    class ProgramA
    {
        public void main()
        {

            string[] s = Console.ReadLine().Split(' ');
            int a = int.Parse(s[0]);
            int b = int.Parse(s[1]);
            int c = int.Parse(s[2]);
            int d = int.Parse(s[3]);
            int e = int.Parse(s[4]);

            Console.WriteLine(d + c * 60 - b - a * 60 - e);

        }
    }

    class ProgramB
    {
        public void main()
        {

            string s = Console.ReadLine();

            for(int i = 0;i < s.Length;i++)
            {
                if(s[i] == '?')
                {
                    Console.Write('D');
                }
                else
                {
                    Console.Write(s[i]);
                }
            }
            

        }
    }

    class ProgramC
    {
        public void main()
        {
            


        }
    }

    class Dis
    {
        public int a;
        public long b;
        public Dis(int a, long b)
        {
            this.a = a;
            this.b = b;
        }
    }
}