Java for LeetCode 077 Combinations
Given two integers n and k, return all possible combinations of k numbers out of 1 ... n.
For example,
If n = 4 and k = 2, a solution is:
[
[2,4],
[3,4],
[2,3],
[1,2],
[1,3],
[1,4],
]
public static void main(String args[]) {
List<List<Integer>> list = combine(5, 2);
System.out.println(list.size());
for (List<Integer> alist : list)
System.out.println(alist + "*");
} static public List<List<Integer>> combine(int n, int k) {
List<List<Integer>> list = new ArrayList<List<Integer>>();
if (n <= 0 || k > n)
return list;
dfs(list, n, k, 0);
return list;
} static List<Integer> alist = new ArrayList<Integer>(); static void dfs(List<List<Integer>> list, int n, int k, int depth) {
if (depth >= k) {
list.add(new ArrayList<Integer>(alist));
return;
}
if (depth == 0)
for (int i = 1; i <= n - k + 1; i++) {
alist.add(i);
dfs(list, n, k, depth + 1);
alist.remove(alist.size() - 1);
}
else
for (int i = 1; i <= n - alist.get(alist.size() - 1) + k - depth - 1; i++) {
alist.add(alist.get(alist.size() - 1) + i);
dfs(list, n, k, depth + 1);
alist.remove(alist.size() - 1);
}
}
Java for LeetCode 077 Combinations的更多相关文章
- Java for LeetCode 090 Subsets II
Given a collection of integers that might contain duplicates, nums, return all possible subsets. Not ...
- Java for LeetCode 216 Combination Sum III
Find all possible combinations of k numbers that add up to a number n, given that only numbers from ...
- Java for LeetCode 214 Shortest Palindrome
Given a string S, you are allowed to convert it to a palindrome by adding characters in front of it. ...
- Java for LeetCode 212 Word Search II
Given a 2D board and a list of words from the dictionary, find all words in the board. Each word mus ...
- Java for LeetCode 211 Add and Search Word - Data structure design
Design a data structure that supports the following two operations: void addWord(word)bool search(wo ...
- Java for LeetCode 210 Course Schedule II
There are a total of n courses you have to take, labeled from 0 to n - 1. Some courses may have prer ...
- Java for LeetCode 200 Number of Islands
Given a 2d grid map of '1's (land) and '0's (water), count the number of islands. An island is surro ...
- Java for LeetCode 188 Best Time to Buy and Sell Stock IV【HARD】
Say you have an array for which the ith element is the price of a given stock on day i. Design an al ...
- Java for LeetCode 154 Find Minimum in Rotated Sorted Array II
Suppose a sorted array is rotated at some pivot unknown to you beforehand. (i.e., 0 1 2 4 5 6 7 migh ...
随机推荐
- 【CodeForces 625C】K-special Tables
题意 把1到n*n填在n*n的格子里.要求每一行都是递增的,使第k列的和最大. 分析 第k列前的格子1 2 .. 按要求填到满格,然后第k列及后面的格子,都从左到右填递增1的数. 第k列的和再加起来, ...
- Fence 设备
RHCS中必须有Fence设备,在设备为知故障发生时,Fence负责让占有浮动资源的设备与集群断开. REDHAT的fence device有两种, 内部fence设备: IBM RSAII卡,HP的 ...
- android HDMI 清晰度 分辨率
但改变分辨率时,发送广播即可: Intent intent_outputmode_change = new Intent(ACTION_OUTPUTMODE_CHANGE); intent_o ...
- std::shared_ptr(二)
Defined in header <memory> template< class T > class shared_ptr; (since C++11) ...
- linux(Debian)下安装与MySql的安装、卸载、配置及使用
参考资料:http://www.cnblogs.com/xusir/p/3334217.html 以下是简要记录. 一.安装 安装:apt-get install mysql-server mysql ...
- JS参考书籍
参考书籍 初级读物:<JavaScript高级程序设计>:一本非常完整的经典入门书籍,被誉为JavaScript圣经之一,详解的非常详细,最新版第三版已经发布了,建议购买. 中级读物:&l ...
- 锋利的jQuery-4--$(document).ready()和window.onload方法的区别
jQuery中的$(document).ready()和JavaScript中的window.onload方法主要有两个方面的不同: 1.执行时机: onload : 网页中所有的元素和元素的关联文件 ...
- CentOS 6.6编译安装Nginx1.6.2+MySQL5.6.21+PHP5.6.3(转)
vi /etc/sysconfig/iptables #编辑防火墙配置文件 # Firewall configuration written by system-config-firewall # M ...
- Linux的一些基础
想要知道你的 Linux 支持的文件系统有哪些,可以察看底下这个目录: [root@www ~]# ls -l /lib/modules/$(uname -r)/kernel/fs 系统目前已加载到内 ...
- 混合应用中的javascript实践
混合应用中的javascript实践 混合应用(hybird app) 在几年前便进入大众视野,近来更是越发风生水起,深受人民群众的喜爱. 目录 概念 什么是混合应用 混合方式 交互 方法注入 参数传 ...