水一个代码: #include <iostream> using namespace std; int n, a; bool ok; bool prime (int x) { ; i * i <= x; i++) ) return false; return true; } int main() { cin >> n; while (n--) { cin >> a; ok = false; ; i * i <= a; i++) ) if (prime (a…

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…

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…

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…

题目链接: 传送门 Sum of Consecutive Prime Numbers 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 intege…

Sieve of Eratosthenes (素数筛选算法) Given a number n, print all primes smaller than or equal to n. It is also given that n is a small number. For example, if n is 10, the output should be “2, 3, 5, 7″. If n is 20, the output should be “2, 3, 5, 7, 11, 13,…

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-…

题目链接:Codeforces 385C Bear and Prime Numbers 这题告诉我仅仅有询问没有更新通常是不用线段树的.或者说还有比线段树更简单的方法. 用一个sum数组记录前n项和,这个sum数组在打素数表时候就能够求出来,注意一点求素数的内层循环要改成i.不能再写成i + i或者i * i了.原因想想就明确了. 这学期最后一场比赛也结束了,结果不非常惬意但也还好. 总的来说这学收获还是蛮多的. 近期可能就不再做ACM了吧,可能要复习CET6了吧,可能要复习期末考试的内容了吧.…

POJ2739 Sum of Consecutive Prime Numbers 题目大意:给出一个整数,如果有一段连续的素数之和等于该数,即满足要求,求出这种连续的素数的个数 水题:艾氏筛法打表+尺取法区间推进,0ms水过(注意循环的终止条件) #include <cstdio> #include <cstdlib> #include <cstring> #include <cmath> #include <ctime> #include &l…

Alexandra and Prime Numbers Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 1658    Accepted Submission(s): 565 Problem Description Alexandra has a little brother. He is new to programming. One…