Algorithms Index

less than 1 minute read

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This is the central index for the C++ algorithms series.

Core

  1. Basic Algorithms
  2. Trees
  3. Disjoint Set Union

Graph Algorithms

  1. Shortest Path and MST
  2. Topological Sort and SCC

Array and Pointer Patterns

  1. Sliding Window and Two Pointers
  2. Monotonic Stack and Deque
  3. Binary Search Patterns

Dynamic Programming and Strings

  1. Dynamic Programming
  2. String Algorithms

Range Data Structures

  1. Segment Tree and Fenwick Tree

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DP stores answers to subproblems so each state is solved once. Core idea: define state and transition. How it works: dp[i] = dp[i-1] + dp[i-2].

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Lower Bound

Lower bound returns first index where value is >= target. Core idea: maintain answer in [left, right) search space. How it works: if nums[mid] < target, move left side up; else shrink right.