题意: 给出一个数组,元素有正有负有0,问其区间和小于 t 的子区间的个数. sum[ r ]-sum[ l-1 ]<t,其中sum是a的前缀和. 实现的方法就是从前往后对于每一个sum[ i ],看在它前面有多少个大于等于sum[ i ] - t 的前缀和. 树状数组维护的是 i 前面有几个数小于等于它 #include <cstdio> #include <cstring> #include <queue> #include <cmath> #in…
D. Petya and Array time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Petya has an array aa consisting of nn integers. He has learned partial sums recently, and now he can calculate the sum o…
Petya loves lucky numbers. Everybody knows that lucky numbers are positive integers whose decimal representation contains only the lucky digits 4 and 7. For example, numbers 47, 744, 4 are lucky and 5, 17, 467 are not. Petya has an array consisting o…
GCD Array Time Limit: 11000/5500 MS (Java/Others) Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 843 Accepted Submission(s): 205 Problem Description Teacher Mai finds that many problems about arithmetic function can be reduced to…
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.…
题目链接: 传送门 Minimum Inversion Number Time Limit: 1000MS Memory Limit: 32768 K Description The inversion number of a given number sequence a1, a2, ..., an is the number of pairs (ai, aj) that satisfy i < j and ai > aj. For a given sequence of numbe…
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…
Different GCD Subarray Query 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. One day, he comes up with a…
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…
Bubble Sort Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 853 Accepted Submission(s): 504 Problem Description P is a permutation of the integers from 1 to N(index starting from 1).Here is t…
Description You are working for Macrohard company in data structures department. After failing your previous task about key insertion you were asked to write a new data structure that would be able to return quickly k-th order statistics in the array…
Description Suppose that the fourth generation mobile phone base stations in the Tampere area operate as follows. The area is divided into squares. The squares form an S * S matrix with the rows and columns numbered from 0 to S-1. Each square contain…
F. A Heap of Heaps time limit per test 3 seconds memory limit per test 512 megabytes input standard input output standard output Andrew skipped lessons on the subject 'Algorithms and Data Structures' for the entire term. When he came to the final tes…
