changelog.md

• make minesweeper
• code a simple one cell solver:
  • COND 1: if a cell's value == flags around it, clear all unrevealed, unflagged tiles
  • COND 2: if a cell's value == flags around it + unrevealed tiles, flag all unrevealed tiles
• now we can run our solve:
  • open a random cell
  • add all "new" tiles to the queue
  • take something off the queue:
    • run the simple one cell solver
    • all revealed tiles get added onto the queue
    • repeat
• Optimization #1:
  • if we flag a tile, surrounding cells should also be added to th queue because their effective mine count changed
• Optimization #2:
  • use a stack instead of a queue to match human solving patterns
• Optimization #3:
  • if we reveal a tile, neighbouring cells may now have COND 2 fulfilled, so we need to add it to the queue
• Optimization #4:
  • subset/reduction, this solves 1-1-safe and 1-2-flag patterns
• Optimization #5:
  • instead of only looking at neighbours, look at cells 2 away as well. unrevealed cells can be shared between neighbours 2 away (e.g. a ? b instead of just a b)