#include<cstdio>
#include<cstring>
#include<algorithm>
#include<functional>
#include<vector>
#include<stack>
#include<queue>
#include<iostream>	
char paro[8][10]={
		"ooossssss",
		"sssooosss",
		"ssssssooo",
		"ossossoss",
		"sossossos",
		"ssossosso",
		"ssosososs",
		"osssossso",
};
char parx[8][10]={
		"xxxssssss",
		"sssxxxsss",
		"ssssssxxx",
		"xssxssxss",
		"sxssxssxs",
		"ssxssxssx",
		"ssxsxsxss",
		"xsssxsssx",
};
using namespace std;
int main(void)
{

	char s[9],cpy[9];
	int tern,ff;
	while(scanf("%s",s)!=EOF) {
		tern=0;
		for(int i=0;i<9;i++) cpy[i]=s[i];
		cpy[9]='\0';
		for(int i=0;i<9;i++) if(cpy[i]=='x') cpy[i]='s';
		for(int i=0;i<8;i++){ 
			if(strcmp(paro[i],cpy)==0) {cout<<"o"<<endl;tern=1;break;};
		}
		ff=0;	
		if(tern==0) {
			for(int i=0;i<9;i++) cpy[i]=s[i];
			cpy[9]='\0';
			for(int i=0;i<9;i++) if(cpy[i]=='o') cpy[i]='s';
			for(int i=0;i<8;i++) 
				if(strcmp(parx[i],cpy)==0) {cout<<"x"<<endl;ff=1;break;};
		}
		if(tern==0 && ff==0) cout<<"d"<<endl;
	}
}
			
		
		
		
		
					