【单选题】The Hydrogen Economy It seems like every day there is a new announcement in the news about automobiles powered by fuel cells. The promises are great, since fuel ceils have the potential to very quickl...
【简答题】以下程序运行时的输出结果是 #include void main { int x=1,y=0; switch(x) { case 1:switch(y) { case 0:printf("**1**");break; case 1:printf("**2**");break; } case 2:printf ("**3**"); }