正在学《0day安全（第二版）》这本书，现在看到堆这一章，空表的内容已经掌握，但是对于快表有以下几个问题不明白，希望大牛们指点。

1.书上说快表和空表的组织结构类似（p148），只是其中的堆块按照单链表组织。但是空表只有8个字节，而书上的快表结构图显示每个快表有48个字节，每一个都为：
00 00 00 00 | 00 00 00 00 | 04 00 00 01 | 00 00 00 00
00 00 00 00 | 00 00 00 00 | 00 00 00 00 | 00 00 00 00
00 00 00 00 | 00 00 00 00 | 00 00 00 00 | 00 00 00 00      （刚初始化后）
      还有就是这里面的每个字节都表示什么？我只知道前4个指向堆块。

2.书上说使用快表之后，偏移0x0688不再是尾块了，而这个位置被快表霸占（p161）。我查看内存后发现这个位置确实变成了上述结构，但是书上标明的Lookaside[0]却在偏移0x06B8处，相差刚好尾48个字节，请问Lookaside[0]上边的这段是什么？如下：
00360688 ：00 00 00 00 | 00 00 00 00 | 04 00 00 01 | 00 00 00 00
00360698 ：00 00 00 00 | 00 00 00 00 | 00 00 00 00 | 00 00 00 00
003606A8 ：00 00 00 00 | 00 00 00 00 | 00 00 00 00 | 00 00 00 00

003606B8 ：00 00 00 00 | 00 00 00 00 | 04 00 00 01 | 00 00 00 00
003606C8 ：00 00 00 00 | 00 00 00 00 | 00 00 00 00 | 00 00 00 00
003606D8 ：00 00 00 00 | 00 00 00 00 | 00 00 00 00 | 00 00 00 00
(书上这段为Lookaside[0])

003606E8 ：00 00 00 00 | 00 00 00 00 | 04 00 00 01 | 00 00 00 00
003606F8 ：00 00 00 00 | 00 00 00 00 | 00 00 00 00 | 00 00 00 00
00360708 ：00 00 00 00 | 00 00 00 00 | 00 00 00 00 | 00 00 00 00
(书上这段为Lookaside[1])

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