Anya and Cubes 搜索+map映射
Anya loves to fold and stick. Today she decided to do just that.
Anya has n cubes lying in a line and numbered from 1 to n from left to right, with natural numbers written on them. She also has k stickers with exclamation marks. We know that the number of stickers does not exceed the number of cubes.
Anya can stick an exclamation mark on the cube and get the factorial of the number written on the cube. For example, if a cube reads 5, then after the sticking it reads 5!, which equals 120.
You need to help Anya count how many ways there are to choose some of the cubes and stick on some of the chosen cubes at most k exclamation marks so that the sum of the numbers written on the chosen cubes after the sticking becomes equal to S. Anya can stick at most one exclamation mark on each cube. Can you do it?
Two ways are considered the same if they have the same set of chosen cubes and the same set of cubes with exclamation marks.
The first line of the input contains three space-separated integers n, k and S (1 ≤ n ≤ 25, 0 ≤ k ≤ n, 1 ≤ S ≤ 1016) — the number of cubes and the number of stickers that Anya has, and the sum that she needs to get.
The second line contains n positive integers ai (1 ≤ ai ≤ 109) — the
numbers, written on the cubes. The cubes in the input are described in
the order from left to right, starting from the first one.
Multiple cubes can contain the same numbers.
Output
Output the number of ways to choose some number of cubes
and stick exclamation marks on some of them so that the sum of the
numbers became equal to the given number S.
Examples
2 2 30
4 3
1
2 2 7
4 3
1
3 1 1
1 1 1
6
Note
In the first sample the only way is to choose both cubes and stick an exclamation mark on each of them.
In the second sample the only way is to choose both cubes but don't stick an exclamation mark on any of them.
In the third sample it is possible to choose any of the cubes in three ways, and also we may choose to stick or not to stick the exclamation mark on it. So, the total number of ways is six.

#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cstdlib>
#include<cstring>
#include<string>
#include<cmath>
#include<map>
#include<set>
#include<vector>
#include<queue>
#include<bitset>
#include<ctime>
#include<time.h>
#include<deque>
#include<stack>
#include<functional>
#include<sstream>
//#include<cctype>
//#pragma GCC optimize(2)
using namespace std;
#define maxn 200005
#define inf 0x7fffffff
//#define INF 1e18
#define rdint(x) scanf("%d",&x)
#define rdllt(x) scanf("%lld",&x)
#define rdult(x) scanf("%lu",&x)
#define rdlf(x) scanf("%lf",&x)
#define rdstr(x) scanf("%s",x)
#define mclr(x,a) memset((x),a,sizeof(x))
typedef long long ll;
typedef unsigned long long ull;
typedef unsigned int U;
#define ms(x) memset((x),0,sizeof(x))
const long long int mod = 1e9 + 7;
#define Mod 1000000000
#define sq(x) (x)*(x)
#define eps 1e-5
typedef pair<int, int> pii;
#define pi acos(-1.0)
//const int N = 1005;
#define REP(i,n) for(int i=0;i<(n);i++)
typedef pair<int, int> pii; inline int rd() {
int x = 0;
char c = getchar();
bool f = false;
while (!isdigit(c)) {
if (c == '-') f = true;
c = getchar();
}
while (isdigit(c)) {
x = (x << 1) + (x << 3) + (c ^ 48);
c = getchar();
}
return f ? -x : x;
} ll gcd(ll a, ll b) {
return b == 0 ? a : gcd(b, a%b);
}
int sqr(int x) { return x * x; } /*ll ans;
ll exgcd(ll a, ll b, ll &x, ll &y) {
if (!b) {
x = 1; y = 0; return a;
}
ans = exgcd(b, a%b, x, y);
ll t = x; x = y; y = t - a / b * y;
return ans;
}
*/ int n, K;
int val[maxn];
ll sum;
ll ans;
typedef pair<ll, int>pli;
map<pli, int>a, b;
ll fac[25]; void dfs1(ll res, int pos, int k) {
if (res > sum)return;
if (k > K)return;
if (pos > n / 2) {
a[pli(res, k)]++; return;
}
dfs1(res, pos + 1, k); dfs1(res + val[pos], pos + 1, k);
if (val[pos] <= 20) {
dfs1(res + fac[val[pos]], pos + 1, k + 1);
}
} void dfs2(ll res, int pos, int k) {
if (res > sum)return;
if (k > K)return;
if (pos > n) {
b[pli(res, k)] ++; return;
}
dfs2(res, pos + 1, k); dfs2(res + val[pos], pos + 1, k);
if (val[pos] <= 20) {
dfs2(res + fac[val[pos]], pos + 1, k + 1);
}
} int main()
{
// ios::sync_with_stdio(0);
fac[1] = fac[0] = 1ll;
for (int i = 2; i <= 20; i++)fac[i] = fac[i - 1] * i;
cin >> n >> K >> sum;
for (int i = 1; i <= n; i++)rdint(val[i]);
dfs1(0, 1, 0); dfs2(0, n / 2 + 1, 0);
map<pli, int>::iterator it;
for (it = a.begin(); it != a.end(); it++) {
int j = (*it).first.second;
for (int i = 0; i + j <= K; i++) {
if (b.count(make_pair(sum - (*it).first.first, i))) {
ans += 1ll * (*it).second*(b[pli(sum - (*it).first.first, i)]);
}
}
}
cout << ans * 1ll << endl;
return 0;
}
Anya and Cubes 搜索+map映射的更多相关文章
- ZOJ 3644 Kitty's Game dfs,记忆化搜索,map映射 难度:2
http://acm.zju.edu.cn/onlinejudge/showProblem.do?problemId=4834 从点1出发,假设现在在i,点数为sta,则下一步的点数必然不能是sta的 ...
- Codeforces Round #297 (Div. 2)E. Anya and Cubes 折半搜索
Codeforces Round #297 (Div. 2)E. Anya and Cubes Time Limit: 2 Sec Memory Limit: 512 MBSubmit: xxx ...
- POJ2503——Babelfish(map映射+string字符串)
Babelfish DescriptionYou have just moved from Waterloo to a big city. The people here speak an incom ...
- map——映射(message.cpp)
信息交换 (message.cpp) [题目描述] Byteland战火又起,农夫John派他的奶牛潜入敌国获取情报信息. Cow历尽千辛万苦终于将敌国的编码规则总结如下: 1 编码是由大写字母组成的 ...
- filter过滤器与map映射
filter过滤器 >>> list(filter(None,[0,1,2,True,False])) [1, 2, True] filter的作用就是后面的数据按照前面的表达式运算 ...
- map映射
采集于:https://blog.csdn.net/luanpeng825485697/article/details/78056312 映射map: var map = new Map(); //映 ...
- Java精选笔记_集合【Map(映射)接口】
Map(映射)接口 简介 该集合存储键值对,一对一对的往里存,并且键是唯一的.要保证map集合中键的唯一性. 从Map集合中访问元素时,只要指定了Key,就能找到对应的Value. 关键字是以后用于检 ...
- UVA12096 - The SetStack Computer(set + map映射)
UVA12096 - The SetStack Computer(set + map映射) 题目链接 题目大意:有五个动作: push : 把一个空集合{}放到栈顶. dup : 把栈顶的集合取出来, ...
- PHP转Go系列:map映射
映射的定义 初识映射会很懵,因为在PHP中没有映射类型的定义.其实没那么复杂,任何复杂的类型在PHP中都可以用数组表示,映射也不例外. $array['name'] = '平也'; $array['s ...
随机推荐
- java8新特性-lambda表达式和stream API的简单使用
一.为什么使用lambda Lambda 是一个 匿名函数,我们可以把 Lambda表达式理解为是 一段可以传递的代码(将代码像数据一样进行传递).可以写出更简洁.更灵活的代码.作为一种更紧凑的代码风 ...
- jquery中选中复选框1.8之前与1.8之后的区别
在jquery 1.8.x中的版本,我们对于checkbox的选中与不选中操作如下: 判断是否选中 $('#checkbox').prop('checked') 设置选中与不选中状态: $('#che ...
- Unable to find required classes (javax.activation.DataHandler and javax.mail.internet.MimeMultipart)
在接触WebService时值得收藏的一篇文章: 在调试Axis1.4访问WebService服务时,出现以下错误: Unable to find required classes (javax.ac ...
- Linux 2.6.32内核字符设备驱…
引言:Linux驱动中,字符设备的设计一般会占产品驱动开发的90%以上,作者根据驱动开发的实际经验,总结了一个标准的字符设备驱动的模板,仅供参考. //=======================字 ...
- Usage of API documented as @since 1.8+”报错的解决办法
参考资料 1.https://blog.csdn.net/a499477783/article/details/78967586/
- 对get post请求的封装
HttpUtil.java package com.dhc.task.wx.util; import java.io.BufferedReader; import java.io.IOExceptio ...
- eclipse egit(分支管理 下)
在Git的分支merge中,不可能没有代码的冲突问题,特别在跟别人分工合作时.那该怎么解决? 1.新建一个conflict分支,在dev方法下添加一句 System.out.println(“Crea ...
- mysql 主键
什么是主键 表中的每一行都应该具有可以唯一标识自己的一列(或一组列).而这个承担标识作用的列称为主键. 任何列都可以作为主键,只要它满足以下条件: • 任何两行都不具有相同的主键值.就是说这列的值都是 ...
- c语言入门教程
https://www.youtube.com/playlist?list=PLY_qIufNHc293YnIjVeEwNDuqGo8y2Emx 感觉这个教程不错
- MYSQL优化——索引覆盖
索引覆盖:如果查询的列恰好是索引的一部分,那么查询只需要在索引文件上进行,不需要进行到磁盘中找数据,若果查询得列不是索引的一部分则要到磁盘中找数据. 建表: create table test_ind ...