at it from the view of the accused, under New York law, his right to appeal from a conviction for the lesser degree can only be exercised at the risk of being reprosecuted for the greater charge as well as the lesser charge if the appeal is successful, even though the state had once failed to obtain a conviction on the greater charge.  This places the accused in a dilemma which was described by the Supreme Court in Green v. United States, supra, 355 U.S. at 193, 78 S.Ct. 221, as 'incredible,' and which is, to be sure, no less incredible because it was devised by New York rather than the federal government.  By placing this unconscionable premium upon a successful appeal by an accused, aconviction for second degree murder and it attacked, not the conviction it had obtained, but the one it had failed to obtain-- the silence of the jury on the first degree murder charge.24  Reversal on the state's appeal meant that the state had been prejudiced by substantial legal error, or to put it another way, the state's failure to obtain a guilty verdict on the first degree murder charge was in part infected by substantial legal error.  To permit the state to reprosecute the accused for the greater charge in these circumstances was to provide the state with an opportunity 'to do better a second time' only because it had been prejudiced by substantial legal error the first time, not because it simply failed to succeed