fun main(args: Array<String>) {
    val s = readLine()!!
    if (s.length % 2 == 1) {
        println("No")
        return
    }

    for (i in s.indices step 2) {
        if (!(s[i] == 'h' && s[i + 1] == 'i')) {
            println("No")
            return
        }
    }

    println("Yes")
}

fun readInteger() = readLine()!!.toInt()
fun readLong() = readLine()!!.toLong()
fun readStringList() = readLine()!!.split(" ")
fun readIntegerList() = readStringList().map(String::toInt)
fun readLongList() = readStringList().map(String::toLong)
