#include<stdio.h>
int main()
{
	char a, b;
	
	scanf("%c %c", &a, &b);
	
	/*
	If a=H, AtCoDeer is honest; if a=D, AtCoDeer is dishonest. 
	If b=H, AtCoDeer is saying that TopCoDeer is honest; if b=D, AtCoDeer is saying that TopCoDeer is dishonest.
	*/
	
	if((a=='H' && b=='H') || (a=='D' && b=='D')){
		printf("H\n");
	}
	
	else printf("D\n");
	
	
	return 0;
}