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"));