一、内容 The alphabet of Freeland consists of exactly N letters. Each sentence of Freeland language (also known as Freish) consists of exactly M letters without word breaks. So, there exist exactly N^M d

题目链接：https://vjudge.net/problem/POJ-1625   Censored! Time Limit: 5000MS Memory Limit: 10000KTotal Submissions: 10870 Accepted: 2979 Description The alphabet of Freeland consists of exactly N lette

某国有N个字母，每句有M个字母，p种字母组合不能出现在句子中。求有多少句子能用。