"""
author : halo2halo
date : 31, Jan, 2020
"""

import sys

# import itertools
# import numpy as np

read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines
sys.setrecursionlimit(10 ** 7)

a, b = read().decode('utf8').split()

print('H' if a==b else 'D')

731b0a979ccafbcd2d3890cfaefccbe1b01f9ace
<mask token>

<mask token>
sys.setrecursionlimit(10 ** 7)
<mask token>
print('H' if a == b else 'D')

<mask token>
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines
sys.setrecursionlimit(10 ** 7)
a, b = read().decode('utf8').split()
print('H' if a == b else 'D')

<mask token>
import sys
read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines
sys.setrecursionlimit(10 ** 7)
a, b = read().decode('utf8').split()
print('H' if a == b else 'D')

"""
author : halo2halo
date : 31, Jan, 2020
"""

import sys

# import itertools
# import numpy as np

read = sys.stdin.buffer.read
readline = sys.stdin.buffer.readline
readlines = sys.stdin.buffer.readlines
sys.setrecursionlimit(10 ** 7)

a, b = read().decode('utf8').split()

print('H' if a==b else 'D')
