21.程P0和进程Pl的共享变量定义及其初值为boolean flag[2 ];int turn = 0;flag[0] = false; flag[l] = false;&<13;
若进行P0和Pl访问临界资源的类c代码实现如下:
void P0()//进程 P0 while(true) {flag[0] = true; turn = 1;while (flag[1] && (turn = = 1)) ; 临界区;flag[0] = false;}&<13;
void P1()//进程 P1while(true) {flag[1] = true; turn = 0;while (flag[0] && (turn = = 0)) ; 临界区;flag[1] = false;}&<13;
则下列选项表达正确的是()(5.0分)