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 Python (3.8.2) (judge verdict: Runtime Error)

S = list(input())
lon = len(S)
count = 0
num = S.count("?")

if S == "?":
  print("D")
if S == "P?":
  print("PD")
if S == "D?":
  print("DD")
if S == "?D":
  print("PD")
if S == "?P":
  print("DP")

#print(S)

if S[0] == "?":
  if S[1] == "D":
    S[0] = "P"
  else:
    S[0] = "D"
    
if S[-1] == "?":
  if S[-2] == "P":
    S[-1] = "D"
  else:
    S[-1] = "D"
    
    
for i in range(1, lon-1):
  if S[i] == "?":
    if S[i-1] == "P":
      S[i] = "D"
    elif S[i-1] == "D":
      S[i] = "P"

    
T = "".join(S)
#print(T.count("D") + T.count("PD") )
print(T)