Question

Given an unsorted array return whether an increasing subsequence of length 3 exists or not in the array.

Formally the function should:

Return true if there exists i, j, k

such that arr[i] < arr[j] < arr[k] given 0 ≤ i < j < k ≤ n-1 else return false.

Your algorithm should run in O(n) time complexity and O(1) space complexity.

Examples:

Given [1, 2, 3, 4, 5],

return true.

Given [5, 4, 3, 2, 1],

return false.

Solution

数学逻辑。

Code

class Solution {
public:
bool increasingTriplet(vector<int>& nums) {
int c1 = INT_MAX, c2 = INT_MAX;
for (int i : nums) {
if (i <= c1) // 当前最小的数
c1 = i;
else if (i <= c2) // 第二或者第三大的数
c2 = i;
else // 如果存在一个比当前最小的大,且比第二大的数大(能够成为第二大,说明它之前有比它小的),那么这个数前面肯定有两个比它小的
return true;
}
return false; }
};

LeetCode——Increasing Triplet Subsequence的更多相关文章

  1. [LeetCode] Increasing Triplet Subsequence 递增的三元子序列

    Given an unsorted array return whether an increasing subsequence of length 3 exists or not in the ar ...

  2. Leetcode: Increasing Triplet Subsequence

    Given an unsorted array return whether an increasing subsequence of length 3 exists or not in the ar ...

  3. 【LeetCode】334. Increasing Triplet Subsequence 解题报告(Python)

    [LeetCode]334. Increasing Triplet Subsequence 解题报告(Python) 标签(空格分隔): LeetCode 题目地址:https://leetcode. ...

  4. [LeetCode] 334. Increasing Triplet Subsequence 递增三元子序列

    Given an unsorted array return whether an increasing subsequence of length 3 exists or not in the ar ...

  5. 【LeetCode】Increasing Triplet Subsequence(334)

    1. Description Given an unsorted array return whether an increasing subsequence of length 3 exists o ...

  6. 【leetcode】Increasing Triplet Subsequence

    Given an unsorted array return whether an increasing subsequence of length 3 exists or not in the ar ...

  7. [Swift]LeetCode334. 递增的三元子序列 | Increasing Triplet Subsequence

    Given an unsorted array return whether an increasing subsequence of length 3 exists or not in the ar ...

  8. Increasing Triplet Subsequence

    Given an unsorted array return whether an increasing subsequence of length 3 exists or not in the ar ...

  9. LeetCode-334. Increasing Triplet Subsequence

    Description: Given an unsorted array return whether an increasing subsequence of length 3 exists or ...

随机推荐

  1. intellij idea 主题更换(换黑底或白底)

    更换主题: File-->setting-->Appearance&Behavior-->Appearance Intellij:白底黑字 Darcula:黑底白字

  2. 模拟hadoop-rpc通信

    一.RPC服务类 package com.css.rpc.server; import java.io.IOException; import org.apache.hadoop.HadoopIlle ...

  3. requests+BeautifulSoup详解

    简介 Python标准库中提供了:urllib.urllib2.httplib等模块以供Http请求,但是,它的 API 太渣了.它是为另一个时代.另一个互联网所创建的.它需要巨量的工作,甚至包括各种 ...

  4. mysql数据池设置

    参考链接https://www.cnblogs.com/KKSoft/p/8040374.html python的数据库连接池包:DBUtils DBUtils提供两种外部接口: Persistent ...

  5. mysql 约束条件 auto_increment 自动增长 清空表 自动增长情况

    清空表情况: mysql> delete from t20; Query OK, rows affected (0.00 sec) mysql> show create table t20 ...

  6. 002-shell变量定义、使用、字符串、数组、注释

    一.变量定义 定义变量时,变量名不加美元符号($) name="lhx" 注意,变量名和等号之间不能有空格.同时,变量名的命名须遵循如下规则: 命名只能使用英文字母,数字和下划线, ...

  7. Matlab GUI memo

    有一段时间没写博客,一周4篇文章都坚持不下来,不知道写哪个方面的内容,写研究相关就怕论文查重查到,其他方面也没太多时间去学.还是花时间多学点其他方面.废话到此,很早就做过matlab gui相关,现在 ...

  8. 模块讲解----os

    os:跟操作系统相关的信息 os模块的增删改查 一.cd进入: windowd: os.chdir("D:/软件/pychar/data/s13") print('获取当前位置:' ...

  9. JAVA_HOME is not defined correctly

    这是个神奇的问题.系统运行着运行着,突然就挂了.各种Java包丢失. 1.检查maven配置 .bash_profile   2.检查运行调取文件  .mavenrc 运行 java -version ...

  10. Safari中的input、textarea无法输入的问题

    原因是这两种表单元素上应用了user-select:none的css属性.一般没人刻意这么做,可能是这样的情况: * { user-select: none; } 在css中排除掉这两种元素就好了: ...