似乎是简单的排列组合问题，但我的算法怎么都对不上啊。可能取决与定义

2 persons: 10*9=90
3 persons: 10*9*8=720
4 persons: 10*9*8*7=5040

total=10*9+10*9*8+10*9*8*7=90+720+5040=5850

but if you disregard the sequence, then it would be like below

2 persons: 10*9/2=45
3 persons: 10*9*8/(3*2)=120
4 persons: 10*9*8*7/(4*3*2)=210
total=45+120+210=375

所有跟帖： 

• 你做对了 -bearsback- ♂ (104 bytes) () 11/15/2014 postreply 16:02:25