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: Accepted)

T = input()
T = "S" + T + "S"

T_list = []
for i in range(len(T)):
    T_list.append(T[i])

for i in range(1,len(T_list)):
    
    if T[i] == "?" :
        if T[i-1] == "P":
            T_list[i] = "D"
        elif T[i+1] == "P":
            T_list[i] = "D"
        elif T[i+1] == "D":
            T_list[i] = "P"
        else:
            T_list[i] = "D"

ans = ""
for t in T_list[1:-1]:
    ans += t
print(ans)