威尔逊定理 HDU2973 YAPTCHA

时间：2017-07-11 01:07:26 阅读：249 评论：0 收藏：0 [点我收藏+]

标签：turned paper output eve pac esc central ext page

YAPTCHA

Time Limit: 10000/5000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 930 Accepted Submission(s): 491

Problem Description

The math department has been having problems lately. Due to immense amount of unsolicited automated programs which were crawling across their pages, they decided to put Yet-Another-Public-Turing-Test-to-Tell-Computers-and-Humans-Apart on their webpages. In short, to get access to their scientific papers, one have to prove yourself eligible and worthy, i.e. solve a mathematic riddle.

However, the test turned out difficult for some math PhD students and even for some professors. Therefore, the math department wants to write a helper program which solves this task (it is not irrational, as they are going to make money on selling the program).

The task that is presented to anyone visiting the start page of the math department is as follows: given a natural n, compute
技术分享

where [x] denotes the largest integer not greater than x.

Input

The first line contains the number of queries t (t <= 10^6). Each query consist of one natural number n (1 <= n <= 10^6).

Output

For each n given in the input output the value of Sn.

Sample Input

Sample Output

Source

Central European Programming Contest 2008

Recommend

lcy

 1 #include<iostream>
 2 #include<cstdio>
 3 #include<cstring>
 4 #include<algorithm>
 5 #include<cmath>
 6 using namespace std;
 7 int t;
 8 bool check[3000010];
 9 int num[1000010];
10 void Eratosthenes(){
11     check[0]=1;
12     check[1]=1;
13     for(int i=2;i<=sqrt(3000010);i++)
14         if(!check[i])
15             for(int j=2*i;j<=3000010;j+=i) check[j]=1;
16 }
17 int main(){
18     scanf("%d",&t);
19     Eratosthenes();
20     for(int i=1;i<=1000000;i++)
21         if(check[3*i+7]) num[i]=num[i-1];
22         else num[i]=num[i-1]+1;
23     int a;
24     for(int i=1;i<=t;i++){
25         scanf("%d",&a);
26         printf("%d\n",num[a]);
27     }
28     return 0;
29 }

威尔逊定理 HDU2973 YAPTCHA

标签：turned paper output eve pac esc central ext page

原文地址：http://www.cnblogs.com/sdfzxh/p/7148177.html

踩

(0)

评论一句话评论（0）

分享档案

更多>

2021年07月29日 (22)
2021年07月28日 (40)
2021年07月27日 (32)
2021年07月26日 (79)
2021年07月23日 (29)
2021年07月22日 (30)
2021年07月21日 (42)
2021年07月20日 (16)
2021年07月19日 (90)
2021年07月16日 (35)

周排行