Inter-universal Teichmuller Theory I ------------------------------------ ・Updated the Acknowledgements ・Corrected a misprint in the notation following the phrase "characterization of the subgroup"  in Example 5.1, (i) ・Corrected a misprint in the 9-th display of Definition 5.2, (viii) Inter-universal Teichmuller Theory II ------------------------------------- ・Updated the Acknowledgements ・Put the "assignment" discussed at the end of Corollary 4.10, (i), in display format