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#include <bits/stdc++.h>
using namespace std;
const int N = 10000810;
int primes[N], cnt;
bool st[N];
void get_primes(int n) {
for (int i = 2; i <= n; i++) {
if (!st[i]) primes[cnt++] = i; //没有被标识过，就增加到质数数组中去
// 线性筛法核心:N 只会被它最小的质因子筛掉
// 从小到大枚举所有可能满足条件的质数
for (int j = 0; primes[j] <= n / i; j++) {
st[primes[j] * i] = true; //从小向大，所以这里可以这么写primes[j],标识st[primes[j] * i]已经标识过了
//最小质因子就可以了，其它质因子放弃掉，看上面的链接里有原因说明
if (i % primes[j] == 0) break;
}
int main() {
get_primes( 1e6 + 10);
for (int i = 0; i < cnt; i++) cout << primes[i] << " ";
return 0;
