Consider this sequence {1, 2, 3, . . . , N}, as a initial sequence of first N natural numbers. You canearrange this sequence in many ways. There will be N! different arrangements. You have to calculatethe number of arrangement of first N natural numbers…
题意:给定 n,m,k,问你在 1 ~ n 的排列中,前 m 个恰好有 k 个不在自己位置的排列有多少个. 析:枚举 m+1 ~ n 中有多少个恰好在自己位置,这个是C(n-m, i),然后前面选出 k 个,是C(m, k),剩下 n - k - i 个是都不在自己位置,也就是错排 D[n-k-i],求一个和就Ok了. 代码如下: #pragma comment(linker, "/STACK:1024000000,1024000000") #include <cstdio>…
Problem UVA1620-Lazy Susan Accept: 81 Submit: 375Time Limit: 3000 mSec Problem Description There are N marbles, which are labeled 1,2,...,N. The N marbles are put in a circular track in an arbitrary order. In the top part of the track there is a “la…
Description There are N<tex2html_verbatim_mark> marbles, which are labeled 1, 2,..., N<tex2html_verbatim_mark> . The N<tex2html_verbatim_mark> marbles are put in a circular track in an arbitrary order. In the top part of the track ther…
I have some (say, n) marbles (small glass balls) and I am going to buy some boxes to store them. Theboxes are of two types:T ype 1: each box costs c1 Taka and can hold exactly n1 marblesT ype 2: each box costs c2 Taka and can hold exactly n2 marblesI…
Problem F Marbles Input: standard input Output: standard output I have some (say, n) marbles (small glass balls) and I am going to buy some boxes to store them. The boxes are of two types: Type 1: each box costs c1 Taka and can hold exactly n1 marble…
