[理工] [離散] 101成大 函數對應
(1) If A={1,2,3,...,10}, the number of functions f:A->A satisfy
f^(1)({1,2,3})=empty set,f^(1)({4,5})={1,3,7}, and f^(1)({8,10})={8,10} is 7776.
101成大單選題2.(A): f^(1)是什麼意思? 7776怎麼求得?
(2) Let A={1,2,3,4,5} and B={u,v,w,x,y}. Determine the number of one-to-one
functions f:A->B where f(1)≠v, w,f(2)≠u, w,f(3)≠x, y and f(4)≠v,x,y
101成大計算題(2): 我用tree列舉應該是14種,有更好的方法?
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