模板——欧拉筛法

/************************************************
* Author        :Powatr
* Created Time  :2015-8-17 10:52:03
* File Name     :欧式筛法.cpp
 ************************************************/

#include <cstdio>
#include <algorithm>
#include <iostream>
#include <sstream>
#include <cstring>
#include <cmath>
#include <string>
#include <vector>
#include <queue>
#include <deque>
#include <stack>
#include <list>
#include <map>
#include <set>
#include <bitset>
#include <cstdlib>
#include <ctime>
using namespace std;

#define lson l, mid, rt << 1
#define rson mid + 1, r, rt << 1 | 1
typedef long long ll;
const int MAXN = 1e5 + 10;
const int INF = 0x3f3f3f3f;
const int MOD = 1e9 + 7;
int N = 1e6+10;

int prime[MAXN];
int check[MAXN];
int tot;
void Eular()//O(n)
{
    tot = 0;
    memset(check, 0, sizeof(check));
    for(int i = 2; i <= N; i++){
         if(!check[i]){
         prime[tot++] = i;
         }
         for(int j = 0 ; j < tot; j++){
            if(i*prime[j] > N) break;
            check[i*prime[j]] = 1;
            if(i%prime[j] == 0) break;
         }
    }
}