Let us consider sets of positive integers less than or equal to n. Note that all elements of a set are different. Also note that the order of elements doesnt matter, that is, both {3, 5, 9} and {5, 9, 3} mean the same set.        Specifying the numbe…

Let us consider sets of positive integers less than or equal to n. Note that all elements of a set are different. Also note that the order of elements doesnt matter, that is, both {3, 5, 9} and {5, 9, 3} mean the same set.        Specifying the numbe…

Equal Sum Sets Let us consider sets of positive integers less than or equal to n. Note that all elements of a set aredifferent. Also note that the order of elements doesnt matter, that is, both {3, 5, 9} and {5, 9, 3} meanthe same set.Specifying the…

Let us consider sets of positive integers less than or equal to n. Note that all elements of a set are different. Also note that the order of elements doesnt matter, that is, both {3, 5, 9} and {5, 9, 3} mean the same set. Specifying the number of se…

UvaLive6661 PDF题目 题意:让你用1~n中k个不同的数组成s,求有多少种组法. 题解: DFS或者DP或打表. 1.DFS 由于数据范围很小,直接dfs每种组法统计个数即可. //#pragma comment(linker, "/STACK:102400000,102400000") #include<cstdio> #include<cmath> #include<iostream> #include<cstring>…

题目链接:http://acm.hust.edu.cn/vjudge/problem/viewProblem.action?id=49406 题意: 输入n,k,s,求在不小于n的数中找出k个不同的数的和等于s的可能性有多少种. 样例: Sample Input9 3 239 3 2210 3 2816 10 10720 8 10220 10 10520 10 1553 4 34 2 110 0 0Sample Output1202015425448100 分析: 用递推的方法把所有的值先求出来…

#include <iostream> #include <cstdio> #include <cstring> #include <cmath> #include <algorithm> #include <string> #include <vector> #include <map> #include <set> #include <time.h> #include <que…

题意: 求从不超过 N 的正整数其中选取 K 个不同的数字,组成和为 S 的方法数. 1 <= N <= 20  1 <= K<= 10  1 <= S <= 155 解题思路: DFS: 因为N,K.S的范围非常小.直接DFS就可以. /* ID: wuqi9395@126.com PROG: LANG: C++ */ #include<map> #include<set> #include<queue> #include<s…

Special subset sums: testing Let S(A) represent the sum of elements in set A of size n. We shall call it a special sum set if for any two non-empty disjoint subsets, B and C, the following properties are true: S(B) ≠ S(C); that is, sums of subsets ca…

Special subset sums: optimum Let S(A) represent the sum of elements in set A of size n. We shall call it a special sum set if for any two non-empty disjoint subsets, B and C, the following properties are true: S(B) ≠ S(C); that is, sums of subsets ca…