xIntro: A -------------------------------------------------------------------------| -------------------------------------------------------------------------| ------------0---------------0-h2-0-------------------------2-------------| ... -----0-1-h2---0-h1-p0---0----------2-1-0-h1-0---0---0-----------2---2h4--| 0-h3------------------3---3-------------------3---3---3-p0------0---0-0--| -------------------------------------------------------------------------|
