SPOJ Prime Generator

// Accepted
// Time: 0.01
// Process: Segmented Seieve

#include<iostream>
#include<cstdio>
#include<cstring>
#include<cmath>
#include<vector>
#include<algorithm>

using namespace std;

typedef long long LL;

#define DIFF 100010
#define mset(c,v) memset(c,v,sizeof(c))
#define sf scanf
#define pf printf

LL prm[DIFF], plen=0;

void sieve(int n)
{
    LL i,j;

    bool mark[DIFF];
    //mset(mark, true);
    for(i=2; i<DIFF; i++) mark[i] = true;

    LL qrt = floor(sqrt(double(n)));

    LL k = floor(sqrt (double(qrt)));

    for(i=2; i<=k; i++)
    {
        if(mark[i])
        {
            for(j=i*i; j<=qrt; j+=i)
            {
                mark[j] = false;
            }
        }
    }

    for(i=2; i<=qrt; i++)
    {
        if(mark[i])
        {
            prm[plen++] = i;
        }
    }

    //for(i=0; i<plen; i++) cout << prm[i] << " ";

    pf("\n");
}

int main()
{
    bool primenow[DIFF];
    int t;
    sf("%d", &t);

    while(t--)
    {
        plen=0;
        LL x , y , p, s, i, j;
        sf("%lld %lld", &x, &y);
        sieve(y);
       // mset(primenow, true);
       for(i=0; i<DIFF; i++) primenow[i] = true;

        for(i=0; i<plen; i++)
        {
            p = prm[i];
            s = x / p;
            s*=p;

            for(j=s; j<=y; j+=p)
            {
                if(j < x) continue;

                primenow[j-x] = false;
            }
        }

        for(i=0; i<plen; i++)
        {
            if(prm[i] >= x and prm[i]<=y)
            {
                pf("%lld\n", prm[i]);
            }
        }

        for(i=0; i<y-x+1; i++)
        {
            if(primenow[i]==true and (i+x) != 1)
            {
                pf("%lld\n", i+x);
            }
        }
    }

    return 0;
}