筛法打素数表

#include <iostream>#include <cstdio>#include <cstring>#include <algorithm>#include <cmath>#include <map>#include <string>#include <cstring>#include <ctime>#define ms(a,b) memset(a,b,sizeof(a))using namespace std;typedef long long ll;const int NP = 1000005;int ispri[NP] = {}, prime[NP], pcnt = 0;void getprime(){    ispri[0] = ispri[1] = 1;    for (long long i = 2; i < NP; i++)        if (ispri[i] == 0)        {            prime[++pcnt] = i;            for (long long j = i * i; j < NP; j += i)            {                ispri[j] = 1;            }        }}int main(){    ///freopen("data.txt", "r", stdin);    freopen("output.txt", "w", stdout);    getprime();    for (int i = 1; i <= pcnt; i++)    {        cout << prime[i] << endl;    }    return 0;}