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 (GCC 9.2.1) (judge verdict: Accepted)

#include <stdio.h>
#include<string.h> 

int main(void)
{
	
	char k[300000];
	int i;
	int len = 0;
	char a = '?';
	char b = 'P';
	char c = 'D';
	
	scanf("%s",k);
	
	len = strlen(k);
		
	for(i= (len - 1); i >= 0; i--){
		//printf("%d",i);
		//scanf("%c", &k[i]);
		if(k[i] == a){
			k[i] = c;
/*			if(i == (len-1)){
				k[i] = c;
			}
			else if(k[i+1] == c){
				k[i] = b;
			}
			else{
				k[i] = c;
			}*/
		}
		//printf("%d",i);
		
	}
	
	//OUT:
	printf("%s", k);
	
	
	return 0;
}