topics.md

1. Variables
   1. Types
   2. Declaration
   3. Scopes
2. Constants
3. Functions
   1. Definition
   2. Declaration
   3. Return values
4. Basic I/O
   1. printf()
   2. scanf()
   3. %d, %c
5. Mathematical operations
   1. Unary operators
      1. ++
      2. --
   2. Binary operators
      1. +
      2. -
      3. *
      4. /
      5. %
   3. math.h
6. Logical operators
   1. &&
   2. ||
7. If-then-else
8. For loops
9. While loops
10. Do-while loops