POJ1306:Combinations
来源:互联网 发布:excel2007数据分析 编辑:程序博客网 时间:2024/06/18 15:13
Description
Computing the exact number of ways that N things can be taken M at a time can be a great challenge when N and/or M become very large. Challenges are the stuff of contests. Therefore, you are to make just such a computation given the following:
GIVEN: 5 <= N <= 100; 5 <= M <= 100; M <= N
Compute the EXACT value of: C = N! / (N-M)!M!
You may assume that the final value of C will fit in a 32-bit Pascal LongInt or a C long. For the record, the exact value of 100! is:
93,326,215,443,944,152,681,699,238,856,266,700,490,715,968,264,381,621, 468,592,963,895,217,599,993,229,915,608,941,463,976,156,518,286,253, 697,920,827,223,758,251,185,210,916,864,000,000,000,000,000,000,000,000
GIVEN: 5 <= N <= 100; 5 <= M <= 100; M <= N
Compute the EXACT value of: C = N! / (N-M)!M!
You may assume that the final value of C will fit in a 32-bit Pascal LongInt or a C long. For the record, the exact value of 100! is:
93,326,215,443,944,152,681,699,238,856,266,700,490,715,968,264,381,621, 468,592,963,895,217,599,993,229,915,608,941,463,976,156,518,286,253, 697,920,827,223,758,251,185,210,916,864,000,000,000,000,000,000,000,000
Input
The input to this program will be one or more lines each containing zero or more leading spaces, a value for N, one or more spaces, and a value for M. The last line of the input file will contain a dummy N, M pair with both values equal to zero. Your program should terminate when this line is read.
Output
The output from this program should be in the form:
N things taken M at a time is C exactly.
N things taken M at a time is C exactly.
Sample Input
100 620 518 60 0
Sample Output
100 things taken 6 at a time is 1192052400 exactly.20 things taken 5 at a time is 15504 exactly.18 things taken 6 at a time is 18564 exactly.
#include <iostream>#include <stdio.h>using namespace std;int main(){ int n,m,i,j,k; double ans; while(cin >> n >> m && (n||m)) { i = n; j = m; k = n-m; ans = 1; while(n) { if(k == 0) k = 1; ans = ans*((double)n/(k*m)); k--; m--; n--; if(!m) m = 1; if(!k) k = 1; } printf("%d things taken %d at a time is %.0lf exactly.\n",i,j,ans); } return 0;}
- poj1306 Combinations
- POJ1306:Combinations
- POJ1306 Combinations
- poj1306解题报告
- POJ1306(组合数公式)
- Combinations
- Combinations
- Combinations
- Combinations
- Combinations
- Combinations
- Combinations
- Combinations
- Combinations
- Combinations
- Combinations
- Combinations
- Combinations
- iOS学习之UINavigationController详解与使用(一)添加UIBarButtonItem
- 从 Java 程序调用 C/C++ 代码
- Oracle中scott用户的由来
- c/c++解析lua配置文件
- C++ 中我们通过定义类来定义自己的数据结构
- POJ1306:Combinations
- uboot烧写到nor flash 上--实验
- Android TabHost用法详解
- C++ builder 通过WMI查询网卡对应的序号
- 【转】非常道-中小软件公司项目管理
- 关于error LNK2019
- C# Sharp FFmpeg
- 赢在数据(R+Hadoop)群电子刊物《数据赢家》第三期出炉
- Hibernate.cfg.xml配置Hibernate连接数据库和对应的数据表