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)

T = input()
ans = []
if T[0]=='?':
    T[0]='D'

for i in range(len(T)-1):
    flg = 1
    if T[i+1]!='?':
        if T[i] != '?':
            ans.append(T[i])
            continue
        else:
            tmp = ans[i-1]
            flg = 0

    if flg:
        tmp = ans[i-1]
    if tmp=='P':
        ans.append('D')
    else:
        ans.append('P')



if T[-1]=='?':
    if ans[-1]=='P':
        ans.append('D')
    else:
        ans.append('P')
else:
    ans.append(T[-1])
print(''.join(ans))