poj 1811 Prime Test

// 给出一个大数(unsigned __int64),判断是否素数,若不是素数,则输出最小的素因子
// 素数判断用miller法 分解用pollard法 

#include <iostream>
#include <time.h>
#include <cmath>
using namespace std;
unsigned __int64 chen(unsigned __int64 x,unsigned __int64 y,unsigned __int64 n)//计算x*y%n
{
    if ((x>>32)==0&&(y>>32)==0) return x*y%n;
    unsigned __int64 a1,b1,a2,b2;
    a1=(x>>32);
    b1=((x<<32)>>32);
    a2=(y>>32);
    b2=((y<<32)>>32);
    unsigned __int64 t1,t2,t3,t4;
    t1=b1*b2%n;t2=b1*a2%n;t3=a1*b2%n;t4=a1*a2%n;
    int i;
    for (i=0;i<32;i++){ t2=(t2<<1)%n;t3=(t3<<1)%n;}
    for (i=0;i<64;i++) t4=(t4<<1)%n;
    return ((t1+t2)%n+(t3+t4)%n)%n;
}
unsigned __int64 mood(unsigned __int64 a,unsigned __int64 u,unsigned __int64 n) //计算a^u%n
{
    unsigned __int64 b,k;
    int i;
    i=k=0;
    while (u>0)
    {
        i++;
        k=(k<<1)+(u&1);
        u>>=1;
    }
    b=1;
    while (i-->0)
    {
        b=chen(b,b,n);
        if (k&1) b=chen(b,a,n);
        k>>=1;
    }
    return b;
}
unsigned __int64 witness(unsigned __int64 a, unsigned __int64 n)//计算a^(n-1)%n 其中如果遇到1的非平凡平方根 就直接返回合数
{
    unsigned __int64 i,x,y,t,u;
    u=n-1;t=0;
    while ((u&1)==0)
    {
        u>>=1;
        t++;
    }
    x=mood(a,u,n);
    for (i=0;i<t;i++)
    {
        y=chen(x,x,n);
        if (y==1&&x!=1&&x!=n-1)
            return x;
        x=y;
    }
    return x;
}
unsigned __int64 miller(unsigned __int64 n)//miller部分 多测几次
{
    int i;
    unsigned __int64 j;

    if (n==2) return 1 ;
    for (i=0;i<50;i++)
    {
        j=rand()%(n-2)+1;
        unsigned __int64 k=witness(j,n);
        if (k!=1)
        {
            return k;
        }
    }
    return 1;
}
unsigned __int64 gcd(unsigned __int64 a,unsigned __int64 b) //最大公约数
{
    unsigned __int64 c;
    if (a<b){c=a;a=b;b=c;}
    while (b!=0)
    {
        c=a;a=b;b=c%b;
    }
    return a;
}
unsigned __int64 pollard(unsigned __int64 n,unsigned __int64 x)//pollard tot用于卡时防止死掉
{
    unsigned __int64 i,k,y,d;
    unsigned __int64 tot=1<<20;
    i=1;y=x;k=2;
    while (1)
    {
        i++;
        tot--;
        x=(chen(x,x,n)-1+n)%n;
        d=gcd((y-x+n)%n,n);
        if (d!=1&&d!=n) return d;
        if (i==k)
        {
            y=x;
            k=(k<<1);
        }
        if (tot==0) return 1;

    }
}
int main()
{
    unsigned __int64 n,m;
    int cass;
    srand(time(0));
    for (cin>>cass;cass>0;cass--)

    {
        scanf("%I64d",&n);

        if (n==2)
            goto isprim;
        if ((n&1)==0)
        {
            cout<<2<<endl;
            continue;
        }

        if (miller(n)==1)
        {
isprim:    cout<<"Prime"<<endl;
            continue;
        }
        unsigned __int64 d=pollard(n,2);
        n/=d;
        unsigned __int64 mind=d;
        if (mind==1) mind=99999999999999;
        while (miller(n)!=1)
        {
            m=rand()%(n-1)+1;
            d=pollard(n,m);
            if (d>1&&mind>d) mind=d;
            n/=d;
        }
        if (mind>n) mind=n;
        printf("%I64d\n",mind);
    }
    return 0;
}