用同步串行队列，控制想要执行的任务挨个执行

#import "dispatchQueueVC.h"@interface dispatchQueueVC ()
@property (strong, nonatomic) dispatch_queue_t ticketQueue;
@property (strong, nonatomic) dispatch_queue_t moneyQueue;
@end@implementation dispatchQueueVC- (void)viewDidLoad {[super viewDidLoad];self.ticketQueue = dispatch_queue_create("ticketQueue", DISPATCH_QUEUE_SERIAL);self.moneyQueue = dispatch_queue_create("moneyQueue", DISPATCH_QUEUE_SERIAL);[self concurrentMoney];[self concurrentSaleTicket];
}- (void)__saveMoney {dispatch_async(self.ticketQueue, ^{[super saveMoney];});}- (void)__drawMoney {dispatch_async(self.ticketQueue, ^{[super drawMoney];});}- (void)__saleTicket {dispatch_async(self.moneyQueue, ^{[super saleTicket];});}- (void)concurrentMoney {dispatch_queue_t queue = dispatch_get_global_queue(0, 0);dispatch_async(queue, ^{for (int i = 0; i < 10; i++) {[self __saveMoney];}});dispatch_async(queue, ^{for (int i = 0; i < 10; i++) {[self __drawMoney];}});
}- (void)concurrentSaleTicket {dispatch_queue_t queue = dispatch_get_global_queue(0, 0);dispatch_async(queue, ^{for (int i = 0; i < 5; i++) {[self __saleTicket];}});dispatch_async(queue, ^{for (int i = 0; i < 5; i++) {[self __saleTicket];}});
}@end