SharedCourses/docs/undergraduate/软件工程学院/计算理论基础/2024-2025学年下学期期末.md

1.3 KiB
Raw Blame History

title
2024-2025学年下学期期末

2025春季学期计算理论基础期末考试试卷回忆版

注:这次考试的形式是五道题自行选四个做, 每题25分, 多做没有加分;此外, 原卷面是英文, 请大家注意

  1. 给出接受以下语言的DFA:
    所有以 1 开头, 能被 5 整除的二进制串, 如 101, 1010, 1111, 左侧(自动机读入的第一个符号)为最高位, 右侧为最低位

  2. 请给出 DFA 化简中 State Elimination Technique 的复杂度的 tight bound, 要有明确的推理过程

  3. A marble is dropped at A and B. Levers x1, x2 and x3 cause the marble tofall either to the left or to the right. Whenever a marble encounters a lever, it causes the lever to reverse after the marble passes, so the next marble will take the opposite branch. The game wins when there is a marble falls through C. The levers are all initialized to the left. Model this toy by a DFA.

    marble

  4. 证明语言 L = \{a^nb^nc^md^m (n \geq m \geq 1) \cup a^nb^mc^md^n (n \geq m \geq 1)\} 不是 CFL

  5. 构造如下的图灵机, 其功能为:给定三个非负整数 n, m, k, 判断 n + m 是否等于 k.

    输入的形式为:

    $\underbrace{11……1}_\text{n个}0\underbrace{11……1}_\text{m个}0\underbrace{11……1}_\text{k个