function Main(input) {
  if (input == "hi"){console.log("%s",'Yes');}
  else if (input == "hihi"){console.log("%s",'Yes');}
  else if (input == "hihihi"){console.log("%s",'Yes');}
  else if (input == "hihihihi"){console.log("%s",'Yes');}
  else if (input == "hihihihihi"){console.log("%s",'Yes');}
  else{console.log("%s",'No');}
}
Main(require("fs").readFileSync("/dev/stdin", "utf8"));