C. Day at the Beach   One day Squidward, Spongebob and Patrick decided to go to the beach. Unfortunately, the weather was bad, so the friends were unable to ride waves. However, they decided to spent their time building sand castles. At the end of th…

C. Propagating tree Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/383/problem/C Description Iahub likes trees very much. Recently he discovered an interesting tree named propagating tree. The tree consists of n nodes numb…

C. Kleofáš and the n-thlon Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/601/problem/C Description Kleofáš is participating in an n-thlon - a tournament consisting of n different competitions in n different disciplines (n…

D. Petya and Array 题目链接:https://codeforces.com/contest/1042/problem/D 题意: 给出n个数,问一共有多少个区间,满足区间和小于t. 题解: 假设目前区间右端点为r,左端点为l,那么由前缀和可得知:sumr-suml-1<t,然后我们再边个形:sumr<t+suml-1,根据这个我们可以发现这有点类似于逆序对. 然后我们就可以用求解逆序对问题的解法来解这个问题了,这里不同的就是每次前面的加上t大于当前这个数即为一对逆序对. 我用…

主题链接:http://codeforces.com/contest/433/problem/B 题目大意:给n(1 ≤ n ≤ 105)个数据(1 ≤ vi ≤ 109),当中有m(1 ≤ m ≤ 105)个问题,分两种.第一种:给出l,r,让你求出v[l],v[r]之间的全部数据和:另外一种:先将原数据升序排序得到vv数组,给出l,r,让你求出vv[l],vv[r]之间的全部数据和: 此题假设用暴力求解,因为数据太大,会TLE,所以利用树状数组,高速求解区间和的问题. 假设不懂树状数组,能够…

C. Propagating tree Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/383/problem/C Description Iahub likes trees very much. Recently he discovered an interesting tree named propagating tree. The tree consists of n nodes numb…

C. Inna and Candy Boxes   Inna loves sweets very much. She has n closed present boxes lines up in a row in front of her. Each of these boxes contains either a candy (Dima's work) or nothing (Sereja's work). Let's assume that the boxes are numbered fr…

D. Mishka and Interesting sum time limit per test 3.5 seconds memory limit per test 256 megabytes input standard input output standard output Little Mishka enjoys programming. Since her birthday has just passed, her friends decided to present her wit…

E. Anton and Permutation time limit per test 4 seconds memory limit per test 512 megabytes input standard input output standard output Anton likes permutations, especially he likes to permute their elements. Note that a permutation of n elements is a…

C. Day at the Beach Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/599/problem/C Description One day Squidward, Spongebob and Patrick decided to go to the beach. Unfortunately, the weather was bad, so the friends were unab…