"use strict";
function main(S) {
   S = S.trim().split("\n");
   if (S === 'hi' || S === 'hihi' || S === 'hihihi' || S === 'hihihihi' || S === 'hihihihihi') {
     console.log('Yes')
   } else {
     console.log('No')
   }
}

main(require('fs').readFileSync('/dev/stdin', 'UTF-8'))