Leetcode - Brainteaser - 319. Bulb Switcher(规律题)
来源:互联网 发布:未来的大数据 编辑:程序博客网 时间:2024/06/05 18:14
1. Problem Description
There are n bulbs that are initially off. You first turn on all the bulbs. Then, you turn off every second bulb. On the third round, you toggle every third bulb (turning on if it's off or turning off if it's on). For the ith round, you toggle every i bulb. For the nth round, you only toggle the last bulb. Find how many bulbs are on after n rounds.
Example:
Given n = 3.
At first, the three bulbs are [off, off, off].
After first round, the three bulbs are [on, on, on].
After second round, the three bulbs are [on, off, on].
After third round, the three bulbs are [on, off, off].
So you should return 1, because there is only one bulb is on.
很常见的一道规律题。一开始所有灯泡都是关着的,第一次(从0开始)每隔一个改变灯泡的状态,第二次每隔两个,第三次每隔三个……以此类推,给出初始灯泡数目n,问n次后剩下几个亮的。
2. My solution
找规律,剩下的都是完全平方数。
class Solution{public: int bulbSwitch(int n) { int i; for(i=1;i*i<=n;i++) ; return i-1; }};
- Leetcode - Brainteaser - 319. Bulb Switcher(规律题)
- Brainteaser:Bulb Switcher
- [leetcode] 319. Bulb Switcher
- leetcode 319. Bulb Switcher
- 319. Bulb Switcher LeetCode
- LeetCode 319. Bulb Switcher
- LeetCode *** 319. Bulb Switcher
- [leetcode]319. Bulb Switcher
- leetcode-319. Bulb Switcher
- leetcode 319. Bulb Switcher
- leetcode 319. Bulb Switcher
- 【leetcode】319. Bulb Switcher
- [Leetcode] 319. Bulb Switcher
- LeetCode-319.Bulb Switcher
- Leetcode 319. Bulb Switcher
- 【LeetCode】319. Bulb Switcher
- [leetcode] 319.Bulb Switcher
- 【leetcode】319. Bulb Switcher
- Java学习提要——字符串连接
- Android环境搭建
- 垃圾陷阱(模拟\dp)
- DeepLearning:三、神经网络
- 93. Restore IP Addresses
- Leetcode - Brainteaser - 319. Bulb Switcher(规律题)
- Android TextView、EditText字符过滤-InputType详解
- FZU 2141 Sub-Bipartite Graph 贪心
- iOS 指定压缩大小(UIImage扩张)--Swift/OC版
- It Can Be Arranged
- Android中的几种多线程实现
- poj 1458 Common Subsequence (LCS模版题)
- APM项目实例解析
- Java锁