http://acm.hdu.edu.cn/showproblem.php?pid=2062 Subset sequence Time Limit: 1000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 3569    Accepted Submission(s): 1802 Problem Description Consider the aggregate An=…

题目链接 Problem Description Consider the aggregate An= { 1, 2, -, n }. For example, A1={1}, A3={1,2,3}. A subset sequence is defined as a array of a non-empty subset. Sort all the subset sequece of An in lexicography order. Your task is to find the m-th…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=2062 Problem Description 考虑集合An = {1,2,...,n}. 例如,A1 = {1},A3 = {1,2,3}. 子集序列被定义为非空子集的数组. 按照字典顺序排列An的所有子集. 你的任务是找到第m个. Input 输入包含多个测试用例. 每个测试用例由两个数字n和m组成(0 <n <= 20,0 <m <= An的子集序列总数). Output 对于每个…

我是把它当做一道数学题来做的. 这篇题解写的有点啰嗦,但是是我最原始的思维过程. 对于一个集合An= { 1, 2, …, n },在n比较小的情况下,在纸上按字典顺序把所有子集排列一下. 以n=3,m=10举例: n=3的情况 容易看出前5个打头的是1,紧接着5个子集打头的是2,最后5个开头的是3. 拿前五个来说,除了第一个,后面四个不看开头的1,后面的排列形式和n=2的子集的排列很相似. f(n)代表集合An所有子集的个数,那么有递推关系: f(n) = n * (f(n - 1) + 1)…

意甲冠军:查找集合{1,2,3...n}第一m一个排列子. 收集的线索所行的大小. 例两个元素的排列子集合按字典树排列是:{1},{1,2},{2},{2,1}: 解法:一个一个元素来确定,每次把剩余的元素按大小顺序排列在num中,然后依据排列组合原理直接计算下一个位置的元素的大小.直到排列数为0停止: 代码: /****************************************************** * author:xiefubao *******************…

这道题目非常好,饶了点儿圈子.我的思路是,先按照组排列.例如,1            2           31 2         2 1        3 11 2 3      2 1 3     3 1 21 3         2 3        3 21 3 2      2 3 1     3 2 1分成3组,每组个数是确定的,因此可以通过m/组数获得第一个数字,然后组数因n--而减小.重新计算属于哪一组,但此时需要考虑printf的数字,因此使用visit数组保证每个数字仅…

Subset sequence Time Limit: 1000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 8188 Accepted Submission(s): 3735 Problem Description Consider the aggregate An= { 1, 2, -, n }. For example, A1={1}, A3={1,2,3}. A…

Problem Description People in Silverland use square coins. Not only they have square shapes but also their values are square numbers. Coins with values of all square numbers up to 289 (=17^2), i.e., 1-credit coins, 4-credit coins, 9-credit coins, ...…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=2069 Problem Description Suppose there are 5 types of coins: 50-cent, 25-cent, 10-cent, 5-cent, and 1-cent. We want to make changes with these coins for a given amount of money.For example, if we have 11…

Problem Description "Well, it seems the first problem is too easy. I will let you know how foolish you are later." feng5166 says."The second problem is, given an positive integer N, we define an equation like this:  N=a[1]+a[2]+a[3]+...+a[m…