# Session 9 — Complexity (Big-O), Pointers, Vectors, Search Methods

## Problems
- "+ -" (two solutions): https://codeforces.com/contest/476/problem/B
- Same idea without an array: https://codeforces.com/problemset/problem/469/A

## Concept reference
- Vectors: https://www.geeksforgeeks.org/cpp/vector-in-cpp-stl/
- See `/Concept_Resources/` for: pointers, binary search, two-pointer
  technique, and complexity/Big-O.

## Recordings
- https://drive.google.com/file/d/1bVsIisY5XdeP1FqH5DsWgGU6DtaWOKAT/view
- https://drive.google.com/file/d/1b18XK9uQQCalxYXNYhOJ4oF888AYQ4as/view