原创 線性dp+倒序思想 Codeforces P859C Pie Rules
Pie Rules You may have heard of the pie rule before. It states that if two people wish to fairly share a slice of p
2020-07-07 15:04:48
原创 權值線段樹+思維 牛客練習賽66 E題 騷區間
騷區間 這種貢獻題可以發現，固定一個右邊界 i ，然後在 1–i-1 找出所有符合條件的左邊界 j ; 所以可以預處理出在 (1–i-1) 中大於 a[i] 的第一個元素位置p1，和第二個元素位置p2, 那麼（p2+1，p1）就是
2020-07-04 17:33:46
原创 二維前綴和思想 Codeforces Good Bye 2015 C題 New Year and Domino
New Year and Domino They say “years are like dominoes, tumbling one after the other”. But would a year fit into a g
2020-07-04 17:33:46
原创 線性dp+數學思維 Codeforces Round #533 (Div. 2) C題 Ayoub and Lost Array
Ayoub and Lost Array Ayoub had an array a of integers of size n and this array had two interesting properties: All
2020-07-04 17:33:46
原创 線性dp Codeforces Round #260 (Div. 1) A題 Boredom
Boredom Alex doesn’t like boredom. That’s why whenever he gets bored, he comes up with games. One long winter eveni
2020-07-04 17:33:46
原创 雙指針+思維 Codeforces Round #354 (Div. 2) C題 Vasya and String
Vasya and String High school student Vasya got a string of length n as a birthday present. This string consists of
2020-07-04 17:33:46
1
原创 樹形dp Codeforces Round #168 (Div. 2) D題 Zero Tree
Zero Tree A tree is a graph with n vertices and exactly n - 1 edges; this graph should meet the following condition
2020-07-04 17:33:46
原创 並查集判環+思維 Codeforces Round #363 (Div. 2) D題 Fix a Tree
Fix a Tree A tree is an undirected connected graph without cycles. Let’s consider a rooted undirected tree with n v
2020-06-25 08:15:32
原创 線段樹+思維 Codeforces Round #197 (Div. 2) D題 Xenia and Bit Operations
Xenia and Bit Operations Xenia the beginner programmer has a sequence a, consisting of 2n non-negative integers: a1
2020-06-25 08:15:32
原创 樹形結構+拓撲思維 Codeforces Round #285 (Div. 2) C題 Misha and Forest
Misha and Forest Let’s define a forest as a non-directed acyclic graph (also without loops and parallel edges). One
2020-06-25 08:15:32
原创 構造思維+樹形結構 Codeforces Round #612 (Div. 2) D題 Numbers on Tree
Numbers on Tree Evlampiy was gifted a rooted tree. The vertices of the tree are numbered from 1 to n. Each of its v
2020-06-20 12:43:05
原创 樹形結構+dp思維 Codeforces Round #247 (Div. 2) C題 k-Tree
k-Tree Quite recently a creative student Lesha had a lecture on trees. After the lecture Lesha was inspired and cam
2020-06-20 12:42:55
原创 01字典樹+貪心 Codeforces Round #613 (Div. 2) D題 Dr. Evil Underscores
Dr. Evil Underscores Today, as a friendship gift, Bakry gave Badawy n integers a1,a2,…,an and challenged him to cho
2020-06-20 12:42:54
原创 並查集判兩點是否連接 [HAOI2006]旅行（洛谷 P2502）
題目描述： n 個點 m 條邊，每條邊都有一個權值，問 s 到 t 路徑上 mx/mi 的最小值，mx，mi分別爲路徑上的最大邊和最小邊； 直接貪心把所有邊由大到小排序，然後依次枚舉每條邊作爲最大邊，然後再枚舉邊作爲加邊，直到
2020-06-15 00:32:52
原创 數學+線性dp 不等數列（洛谷 P2401）
不等數列 題目描述 將1到n任意排列，然後在排列的每兩個數之間根據他們的大小關係插入“>”和“<”。問在所有排列中，有多少個排列恰好有k個“<”。答案對2015取模。 注：1 ~ n的排列指的是1~n這n個數各出現且僅出現一次的數
2020-06-15 00:32:52