说实话,$2200$ 的题做不出来也有点丢脸了…… 当然要先判所有数出现次数相同. 首先区间排序就相当于交换相邻两个数,前面的数要大于后面的数才能交换. 然后就不会了…… 我们考虑 $b_1$ 到 $b_{i-1}$ 都已经归位了,现在要把 $b_i$ 归位. 找到其在 $a$ 中下一次出现的位置(设为 $p$).发现只有当 $a_p$ 是 $a_i$ 到 $a_p$ 的最小值时,才能归到. 具体代码实现时不会改变 $a$ 的位置,那怎么判断最小值呢?发现已经归位的数对最小值没有贡献,可以归位后…

思路: 线段树好题.对a数组中的每个元素从左到右依次操作,判断最终是否能够转化成b数组.在此过程中使用线段树维护区间最小值判断是否能够进行合法操作. 实现: #include <bits/stdc++.h> using namespace std; , INF = 0x3f3f3f3f; deque<int> d[N]; ]; void build(int num, int l, int r) { if (l == r) { tree[num] = a[l]; return; }…

Educational Codeforces Round 67 D. Subarray Sorting 传送门 题意: 给出两个数组\(a,b\),现在可以对\(a\)数组进行任意次排序,问最后能否得到\(b\)数组. \(n\leq 3*10^5,a\leq n.\) 思路: 首先注意到任意次排序可以等价于任意次交换两个相邻的数,当且仅当前一个数不小于后面一个数. 我一开始想的是按权值从小到大来构造,但最终发现这条路走不通. 正解就是比较直接的思路,按位置一个一个来匹配. 对于一个\(b_i\…

Problem You are given an array \(a_1\),\(a_2\),-,\(a_n\) and an array \(b_1\),\(b_2\),-,\(b_n\). For one operation you can sort in non-decreasing order any subarray \(a[l-r]\) of the array \(a\). For example, if \(a=[4,2,2,1,3,1]\) and you choose sub…

题意:给你两个长度为 n 的序列 a 和 b , 可以对 a 进行 操作: 选择一段区间[ l, r ] ,使得序列a 在这段区间里 按升序排序. 可以对a 进行任意多次操作,问 a是否有可能变成b序列. 解: 首先,枚举b序列,然后在a中,找这个元素在a出现的位置(如果是第一次出现的,就找第一次出现的那个位置,第二次出现就找第二次出现的) pos ,然后查询 0 ~ pos 的最小值 (线段树),若 最小值是 b对应的那个元素,就满足,否则,就不满足. 然后若满足,需要更新线段树,把查询的元素…

CF1187D. Subarray Sorting 想要把一个数x换到前面,x一定是小一点的值.由于B串是固定的,A串可调整,我们可以遍历B数组,对于B[i],找到对于在A数组的位子pos,判断1-pos中,是不是A[pos]最小,如果是最小,说明可以换到最前面,把A[pos]的值变为inf后,继续遍历. #include <cstdio> #include <vector> #include <cstring> #include <algorithm> #…

Educational Codeforces Round 67 CF1187B Letters Shop 二分 https://codeforces.com/contest/1187/submission/56313177 CF1187C Vasya And Array 直接构造 https://codeforces.com/contest/1187/submission/56316127 CF1187D Subarray Sorting 这题等System Test后更吧... CF1187E…

2021-10-14 P2577 [ZJOI2004]午餐 2021-10-13 CF815C Karen and Supermarket(小小紫题,可笑可笑) P6748 『MdOI R3』Fallen Lord(sort(a+1,a+1+n,greater<int>()); 真好用) P4161 [SCOI2009]游戏 P1707 刷题比赛 2021-10-12 CF1573A Countdown P2717 寒假作业 P7868 [COCI2015-2016#2] VUDU P1660…

目录 Contest Info Solutions A. Stickers and Toys B. Letters Shop C. Vasya And Array D. Subarray Sorting E. Tree Painting Contest Info Data:2019.6.30 Solved:4/7 Solutions A. Stickers and Toys 题意: 有\(A\)物品\(s\)个,\(B\)物品\(t\)个,现在将这些物品装到\(n\)个箱子里,每个箱子只有一下三…

Given an array nums and a target value k, find the maximum length of a subarray that sums to k. If there isn't one, return 0 instead. Example 1: Given nums = [1, -1, 5, -2, 3], k = 3, return 4. (because the subarray [1, -1, 5, -2] sums to 3 and is th…

Given an array of n positive integers and a positive integer s, find the minimal length of a subarray of which the sum ≥ s. If there isn't one, return 0 instead. For example, given the array [2,3,1,2,4,3] and s = 7,the subarray [4,3] has the minimal…

Find the contiguous subarray within an array (containing at least one number) which has the largest product. For example, given the array [2,3,-2,4],the contiguous subarray [2,3] has the largest product = 6. 这个求最大子数组乘积问题是由最大子数组之和问题演变而来,但是却比求最大子数组之和要复…

Find the contiguous subarray within an array (containing at least one number) which has the largest sum. For example, given the array [−2,1,−3,4,−1,2,1,−5,4],the contiguous subarray [4,−1,2,1] has the largest sum = 6. click to show more practice. Mor…

Problem: Given an array of n positive integers and a positive integer s, find the minimal length of a subarray of which the sum ≥ s. If there isn't one, return 0 instead. For example, given the array [2,3,1,2,4,3] and s = 7,the subarray [4,3] has the…

Find the contiguous subarray within an array (containing at least one number) which has the largest product. For example, given the array [2,3,-2,4],the contiguous subarray [2,3] has the largest product = 6. 子数组乘积最大 class Solution { public: int maxPr…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=2838 Cow Sorting Problem Description Sherlock's N (1 ≤ N ≤ 100,000) cows are lined up to be milked in the evening. Each cow has a unique "grumpiness" level in the range 1...100,000. Since grumpy cow…

Given an array of integers, find a contiguous subarray which has the largest sum. Notice The subarray should contain at least one number. Have you met this question in a real interview? Yes Example Given the array [−2,2,−3,4,−1,2,1,−5,3], the contigu…

Find the contiguous subarray within an array (containing at least one number) which has the largest sum. For example, given the array [−2,1,−3,4,−1,2,1,−5,4],the contiguous subarray [4,−1,2,1] has the largest sum = 6. 题意:就是求最大字数组和. 思路: DP问题,O(n)内可破 对…

1.   Maximum Subarray (#53) Find the contiguous subarray within an array (containing at least one number) which has the largest sum. For example, given the array [-2, 1, -3, 4, -1, 2, 1, -5, 4], the contiguous subarray [4, -1, 2, 1] has the largest s…

Find the contiguous subarray within an array (containing at least one number) which has the largest product. For example, given the array [2,3,-2,4],the contiguous subarray [2,3] has the largest product = 6. 看到这道题,很明显的一套动态规划类型的题目,和最长升序子序列之类的十分类似,那么首先…

Question: Find the contiguous subarray within an array (containing at least one number) that has the largest sum. For example, given the array [2, 1, –3, 4, –1, 2, 1, –5, 4], The contiguous array [4, –1, 2, 1] has the largest sum = 6. 此问题提供了两种解决方案,首先…

<算法导论>一书中演示分治算法的第二个例子,第一个例子是递归排序,较为简单.寻找maximum subarray稍微复杂点. 题目是这样的:给定序列x = [1, -4, 4, 4, 5, -3, -4, 9, 6 - 4, 6, 4, 3, -5]:寻找一个连续的子序列,使得其和是最大. 这个题目有意义的地方在于,序列X的元素有正有负. 思路很简单,把序列分为相同的两部分A和B,在其内寻找maximum subarray,那么maximum subarray有可能在A中,也有可能在B中,也有…

give an array and target value, find the max length of the subarray which sum of the elements is less or equal to that value. public int longestSubArray(int[] a, int k){ if(a==null || a.length==0){ return 0; } int max=0; int len=a.length; for(int i=0…

Maximum Subarray Find the contiguous subarray within an array (containing at least one number) which has the largest sum. For example, given the array [−2,1,−3,4,−1,2,1,−5,4],the contiguous subarray [4,−1,2,1] has the largest sum = 6. More practice:…

1306. Sorting Algorithm Constraints Time Limit: 1 secs, Memory Limit: 32 MB Description One of the fundamental problems of computer science is ordering a list of items. There're a plethora of solutions to this problem, known as sorting algorithms. So…

这题比较简单,重点应该在如何减少循环次数. package practice; import java.io.BufferedInputStream; import java.util.Map; import java.util.Scanner; import java.util.TreeMap; /** * DNA sorting * * @author caiyu * @date 2014-11-5 */ public class POJ1007 { public static void m…

题目链接 http://acm.split.hdu.edu.cn/showproblem.php?pid=5869 Problem Description This is a simple problem. The teacher gives Bob a list of problems about GCD (Greatest Common Divisor). After studying some of them, Bob thinks that GCD is so interesting.…

1,layer是对游戏中所有物体的分类别划分,如UIlayer, waterlayer, 3DModelLayer, smallAssetsLayer, effectLayer等.将不同类的物体划分到不同的层,便于相机拣选,在相机的cullmask中可以选择渲染哪些层,不选择的层则不会渲染.还可以用于射线检测对象的拣选,可以指定只对某些层的对象进行射线检测. 2,canvas默认是屏幕空间的2D对象,在屏幕空间时仅具有sort order属性,当把它设置为世界空间时,sort order属性消失…

题目链接:Maximum Product Subarray solutions同步在github 题目很简单,给一个数组,求一个连续的子数组,使得数组元素之积最大.这是求连续最大子序列和的加强版,我们可以先看看求连续最大子序列和的题目maximum-subarray,这题不难,我们举个例子. 假设数组[1, 2, -4, 5, -1, 10],前两个相加后得到3,更新最大值(为3),然后再加上-4后,和变成-1了,这时我们发现如果-1去加上5,不如舍弃前面相加的sum,5单独重新开始继续往后相加…

WebGrid with filtering, paging and sorting by Jose M. Aguilar on April 24, 2012 in Web Development A few days ago I received some questions on the use of the Webgrid helper in the comments section of my personal blog, specifically on how to implement…