What I wanted to say is that official programs are relatively easy to read because they seem to be standardized. I'm sorry for my poor English.
From which sample you should start depends on your target. If your target is to make RPG, GAME2RPG is the best as your start place. If your target is to calculate planetary orbit of the solar system, mathematics and sin/cos of EX8TECHDEMO is the best.
1そうだね プレイ済み