线程1: EXC_BAD_ACCESS (code=1，address=0xf00000c)

#import <Foundation/Foundation.h>

@interface SharedResource : NSObject {
    int value;
    NSLock *lock;
}
- (void)increment;
- (int)getValue;
@end

@implementation SharedResource
- (instancetype)init {
    self = [super init];
    if (self) {
        value = 0;
        lock = [[NSLock alloc] init];
    }
    return self;
}

- (void)increment {
    [lock lock];
    value++;
    [lock unlock];
}

- (int)getValue {
    [lock lock];
    int temp = value;
    [lock unlock];
    return temp;
}
@end

int main(int argc, const char * argv[]) {
    @autoreleasepool {
        SharedResource *resource = [[SharedResource alloc] init];
        
        // 创建多个线程来访问共享资源
        dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
        for (int i = 0; i < 1000; i++) {
            dispatch_async(queue, ^{
                [resource increment];
            });
        }
        
        // 等待所有任务完成
        dispatch_sync(queue, ^{});
        
        NSLog(@"Final value: %d", [resource getValue]);
    }
    return 0;
}