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PUMaC 2011 · 组合（B 组） · 第 1 题

PUMaC 2011 — Combinatorics (Division B) — Problem 1

专题
Discrete Math / 离散数学
难度
L3
来源
PUMaC

题目详情

  1. [ 3 ] How many ways are there to arrange the five letters P,U,M,A,C, such that the two vowels are not adjacent?
解析
  1. There are − 4 = 6 ways to find the pair of places to put the two vowels in. Then, there 2 are 2! ways to arrange the vowels and 3! ways to arrange the consonants. Thus, the answer is 6 × 2! × 3! = 72 .