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

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