Month: January 2020

answer：190

解法：每人先分2个，剩下18个分3份，用stars and bars，就是20取2（20个stars，2个bars），得190.

Alice has 24 apples. In how many ways can she share them with Becky and Chris so that each of the three people has at least two apples?

小明有24个苹果。他想和小红、小华一起分这24个苹果，要求每人至少分到2个苹果，问有多少种分法？