Module Hitachi2020A

    Sub Main()
        Dim S As String
        Dim i As Integer

        S = Console.ReadLine()

        For i = 0 To S.Length - 1
            If i = S.Length - 1 Then
                Console.Write("No")
                Exit Sub
            End If
            If S.Substring(i, 2) = "hi" Then
                i = i + 1
            Else
                Console.Write("No")
                Exit Sub
            End If
            If i = S.Length Then
                Exit For
            End If
        Next
        Console.Write("Yes")
    End Sub

End Module
