int x=x+y 执行频度为( )\n \n \n \n \n \n \n

\n \n \n \n A.\n 0\n

\n \n

\n \n \n \n B.\n 1\n

\n \n

\n \n \n \n C.\n n\n

\n \n

\n \n \n \n D.\n n2\n