zoukankan      html  css  js  c++  java
  • 2017/11/20 Leetcode 日记

    2017/11/14 Leetcode 日记

    442. Find All Duplicates in an Array

    Given an array of integers, 1 ≤ a[i] ≤ n (n = size of array), some elements appear twice and others appear once.

    Find all the elements that appear twice in this array.

    Could you do it without extra space and in O(n) runtime?

    class Solution {
    public:
        vector<int> findDuplicates(vector<int>& nums) {
            int sz = nums.size();
            int once[sz+2];
            vector<int> num;
            for(int i = 0; i < sz+2; i++){
                once[i] = 0;
            }
            for(int i = 0; i < sz; i++){
                if(once[nums[i]] == 1){
                    num.push_back(nums[i]);
                }else{
                    once[nums[i]] ++;
                }
            }
            return num;
        }
    };
    c++
    class Solution:
        def findDuplicates(self, nums):
            """
            :type nums: List[int]
            :rtype: List[int]
            """
            num = []
            for x in nums:
                if nums[abs(x)-1] < 0:
                    num.append(abs(x))
                else:
                    nums[abs(x)-1] *= -1
            return num
    Python3

    406. Queue Reconstruction by Height

    Suppose you have a random list of people standing in a queue. Each person is described by a pair of integers (h, k), where h is the height of the person and k is the number of people in front of this person who have a height greater than or equal to h. Write an algorithm to reconstruct the queue.

    (先以第一序列升序,第二序列降序排列,再插入表中。)

    vector<pair<int, int>> reconstructQueue(vector<pair<int, int>>& people) {
        auto comp = [](const pair<int, int>& p1, const pair<int, int>& p2)
                        { return p1.first > p2.first || (p1.first == p2.first && p1.second < p2.second); };
        sort(people.begin(), people.end(), comp);
        vector<pair<int, int>> res;
        for (auto& p : people) 
            res.insert(res.begin() + p.second, p);
        return res;
    }
    C++
  • 相关阅读:
    [置顶] 输入子系统
    多线程知识点总结
    mybatis知识点总结
    redis知识点及常见面试题
    spring知识点(面试题)
    【linux】vim常用命令
    Linux常用命令大全
    Java 位运算(移位、位与、或、异或、非)
    图论之堆优化的Prim
    BZOJ3261 最大异或和 解题报告(可持久化Trie树)
  • 原文地址:https://www.cnblogs.com/yoyo-sincerely/p/7833062.html
Copyright © 2011-2022 走看看