function Main(input){
  input = input.split(' ');
  var a = input[0];
  var b = input[1];

  if( a === 'H' && b === 'H' || a === 'D' && b === 'D') {
      console.log('H');
  } else {
  console.log('D');
  }

}
Main(require("fs").readFileSync("/dev/stdin", "utf8"));