如何搞定技术面试编码环节

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编码，是软件工程师必须掌握的技能。以下介绍的方法，帮助软件工程师更顺利的通过技术面试的编码环节。

解决问题的步骤

  1. 听：仔细聆听问题描述，完整获取信息
  2. 举例：注意特殊用例、边界场景
  3. 快速解决：尽快找到解决方案，不一定要最优。想想最优方案是什么样子的，你的最终解决方案可能处于当前方案、最优方案之间
  4. 优化：优化第一版解决方案
    • BUD优化方法
      • 瓶颈，Bottlenecks
      • 不必要的工作，Unnecessary work
      • 重复的工作，Duplicated work
    • Four Algorithm Approaches
      • Pattern Matching: What problems is this similar to?
      • Simplify & Generalize: Tweak and solve simpler problem.
      • Base Case & Build: Does it sound recursive-ish?
      • Data Structure Brainstorm: Try various data structures.
    • 或者尝试下面的方法
      • Look for any unused info
      • Use a fresh example
      • Solve it “incorrectly”
      • Make time vs. space tradeoff
      • Precompute or do upfront work
      • Try a hash table or another data structure
  5. 重新审视解决方案，确保在编码前理解每个细节
  6. 实现
    • Write beautiful code
      • Modularize your code from the beginning
      • Refactor to clean up anything that isn’t beautiful
  7. 测试
    • FIRST Analyze
      • What’s it doing? Why?
      • Anything that looks wired?
      • Error hot spots
    • THEN use test cases
      • Small test cases
      • Edge cases
      • Bigger test cases
    • When you find bugs, fix them carefully.

需要掌握的基础知识

  1. 数据结构：hash tables, linked lists, stacks, queues, trees, tries, graphs, vectors, heaps
  2. 算法：quick sort, merge sort, binary search, breadth-first search, depth-first search
  3. 基础概念：Big-O Time, Big-O Space, Recursion & Memoization, Probability, Bit Manipulation

参考