unittest
{
	assert( [ "hihi" ].parse.expand.solve == "Yes" );
	assert( [ "hi" ].parse.expand.solve == "Yes" );
	assert( [ "ha" ].parse.expand.solve == "No" );
}



import std.conv;
import std.range;
import std.stdio;
import std.typecons;

void main()
{
	stdin.byLineCopy.parse.expand.solve.writeln;
}

auto parse( Range )( Range input )
if( isInputRange!Range && is( ElementType!Range == string ) )
{
	auto s = input.front.to!( dchar[] );
	return tuple( s );
}

auto solve( dchar[] s )
{
	while( !s.empty )
	{
		if( s.length < 2 || s[ 0 .. 2 ] != "hi" ) return "No";
		s.popFrontN( 2 );
	}
	return "Yes";
}
