【leetcode】338. Counting Bits
来源:互联网 发布:双录取很坑人 知乎 编辑:程序博客网 时间:2024/06/06 05:48
题目:
- Total Accepted: 75933
- Total Submissions: 125118
- Difficulty: Medium
- Contributor: LeetCode
Given a non negative integer number num. For every numbers i in the range 0 ≤ i ≤ num calculate the number of 1's in their binary representation and return them as an array.
Example:
For num = 5
you should return [0,1,1,2,1,2]
.
分析:设f(n)是 num = n 时 二进制表示中 1 的 个数。则,f(n) = { f(n-1) + 1 n是奇数
{ f(n\2) n是偶数
因为若n是奇数,则上一个数的末位必为0 , f(n)就等于上一个的"1"的个数加一。 若n是偶数,则相当于f(n/2)左移一位,则1的数量与f(n/2)是一致的。
代码:
#include <iostream>
#include <vector>
using namespace std;
class Solution {
public:
vector<int> countBits(int num) {
vector<int> all(num + 1, 0);
for (int i = 1; i < num + 1; i++) {
if (i % 2 == 0) {
all[i] = all[i / 2];
}
else {
all[i] = all[i - 1] + 1;
}
}
return all;
}
};
阅读全文
0 0
- [leetcode] 338. Counting Bits
- leetcode 338. Counting Bits
- [LeetCode]338. Counting Bits
- LeetCode#338. Counting Bits
- [LeetCode] 338. Counting Bits
- LeetCode 338. Counting Bits
- [LeetCode]338. Counting Bits
- LeetCode-338. Counting Bits
- LeetCode *** 338. Counting Bits
- (leetcode) 338. Counting Bits
- #leetcode#338. Counting Bits
- LeetCode 338. Counting Bits
- leetcode 338. Counting Bits
- LeetCode-338. Counting Bits
- LeetCode-338. Counting Bits
- leetcode-338. Counting Bits
- Leetcode 338. Counting Bits
- LeetCode 338. Counting Bits
- 多线程知识点总结
- 栈的链式结构
- 单向循环链表 通讯录
- Mac上配置Java环境变量
- 初识多线程
- 【leetcode】338. Counting Bits
- 基于激光传感器的移动机器人动态运动检测
- Java程序员修炼之路
- lintcode 56 两数之和
- USACO-Section1.2 palsquare[字符处理]
- 左侧显示分类栏
- 598. Range Addition II
- Maven学习(一)
- linux多线程