function Main(input) {
  input=input.trim();
  var A = input.split(" ")[0];
  var B = input.split(" ")[1];
  if(A == "H"){
    console.log(B);
  }else{
    console.log((B === "H") ? "D" : "H");
  }
}

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