113. Nearly prime numbers time limit per test: 0.25 sec. memory limit per test: 4096 KB Nearly prime number is an integer positive number for which it is possible to find such primes P1 and P2 that given number is equal to P1*P2. There is given a seq…

题目链接:http://poj.org/problem?id=2739 #include <cstdio> #include <cstring> using namespace std; int method[10001][1300]; int dp[10001]; bool isntprime[10001]; int heap[1300],cnt; void calprime(){ method[2][0]=1; dp[2]++; heap[cnt++]=2; for(int i…

Sum of Consecutive Prime Numbers Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 19697   Accepted: 10800 Description Some positive integers can be represented by a sum of one or more consecutive prime numbers. How many such representatio…

How many prime numbers Time Limit: 3000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 12955    Accepted Submission(s): 4490 Problem Description   Give you a lot of positive integers, just to find out how many…

Problem Description Give you a lot of positive integers, just to find out how many prime numbers there are. Input There are a lot of cases. In each case, there is an integer N representing the number of integers to find. Each integer won't exceed 32-…

Sum of Consecutive Prime Numbers Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 25225   Accepted: 13757 Description Some positive integers can be represented by a sum of one or more consecutive prime numbers. How many such representatio…

第一眼看这道题目的时候觉得可能会很难也看不太懂,但是看了给出的Hint之后思路就十分清晰了 Consider the first sample. Overall, the first sample has 3 queries. The first query l = 2, r = 11 comes. You need to count f(2) + f(3) + f(5) + f(7) + f(11) = 2 + 1 + 4 + 2 + 0 = 9. The second query comes…

Time Limit: 1000MS   Memory Limit: 65536K Description Some positive integers can be represented by a sum of one or more consecutive prime numbers. How many such representations does a given positive integer have? For example, the integer 53 has two r…

Codeforces 385C Bear and Prime Numbers 其实不是多值得记录的一道题,通过快速打素数表,再做前缀和的预处理,使查询的复杂度变为O(1). 但是,我在统计数组中元素出现个数时使用了map,以至于后面做前缀和的累加时,每次都要对map进行查询,以至于TLE.而自己一直没有发现,以为是欧拉筛对于这道题还不够优,于是上网搜题解,发现别人的做法几乎一样,但是却能跑过,挣扎了许久才想起是map的原因.map的内部实现是一颗红黑树,每次查询的复杂度为O(logN),在本来时…

Sum of Consecutive Prime Numbers Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 20050   Accepted: 10989 Description Some positive integers can be represented by a sum of one or more consecutive prime numbers. How many such representatio…