Uva 11086 - Composite Prime

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 // Verdict :: Accepted
// Time :: 0.109
#include <iostream>
#include <cstdio>
#include <cstring>
#include <map>
#include <string>
#include <vector>
#include <cmath>
#include <cctype>
#include <sstream>
#include <set>
#include <list>
#include <stack>
#include <queue>
#include <algorithm>
#define sf scanf
#define pf printf
#define sfint scanf ("%d %d",&a,&b)
#define sfl scanf ("%ld %ld",&a,&b)
#define sfll scanf ("%lld %lld",&a,&b)
#define sfd scanf ("%lf %lf",&a,&b)
#define sff scanf ("%f %f",&a,&b)
#define lp1(i,n) for(i=0;i<n;i++)
#define lp2(i,n) for(i=1;i<=n;i++)
#define LL long long
#define L long
#define mem(c,v) memset(c,v,sizeof(c))
#define ui unsigned int
#define ull unsigned long long int
#define nl puts("")
#define sq(x) ((x)*(x))
#define MX 1000005
#define N 100
#define MOD 10000000007
#define pb push_back
#define pi acos(-1.0)
#define sz size()
#define gc getchar ()
#define ps push
#define clr clear
#define inf 2147483647
#define bn begin()
#define ed end()

using namespace std;

LL prime[MX+10];
bool flag[MX+10],not_cp[MX+10];

LL setbit(LL n, LL pos)
{
    n=n|(1<<pos);
    return n;
}

bool checkbit(LL n, LL pos)
{
    n=n&(1<<pos);
    return n;
}

void seieve(LL n)
{
    //mem(flag,false);

    LL i,j,x=(long) sqrt(double(n));

    prime[0]=setbit(prime[0],0);
    prime[0]=setbit(prime[0],1);

    for(i=4;i<=n;i+=2)
    {
        prime[i>>5]=setbit(prime[i>>5],i&31);
        //flag[i]=true;
    }

    for(i=3;i<=x;i+=2)
    {
        if(!checkbit(prime[i>>5],i&31))
        {
            for(j=i*i;j<=n;j+=i)
            {
                prime[j>>5]=setbit(prime[j>>5],j&31);
            }
        }
    }

//    for(i=2;i<=n;i++)
//    {
//        if(!checkbit(prime[i>>5],i&31))
//        {
//            cout << i << " ";
//        }
//    }
}

void not_compo(LL n)
{
    LL i,j; mem(not_cp,false);
    mem(flag,false);

    for(i=4;i<=n;i++)
    {
        if(checkbit(prime[i>>5],i&31) and !not_cp[i])
        {
            for(j=i<<1;j<=n;j+=i)
            {
                not_cp[j]=true;
            }

            flag[i]=true;
        }
    }

//    for(i=1;i<=n;i++)
//    {
//        //cout << flag[i] << " ";
//        if(flag[i])
//        {
//            cout << i << " ";
//        }
//    }
}

int main()
{
    seieve(MX);
    not_compo(MX);

    LL n;
    while(sf("%lld",&n)==1)
    {
        LL cnt=0;

        while(n--)
        {
            LL x;
            sf("%lld",&x);

            if(flag[x])
            {
                cnt+=1;
            }
        }

        pf("%lld\n",cnt);
    }

    return 0;
}

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