bzoj3667 Rabin-Miller算法

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标题写错了，其实这题考pollard-rho。
#include<cstdio>#include<cstdlib>#include<algorithm>using namespace std;#define LL long longint prm[]={2,3,5,7,11,13,17,19,23};LL Rand(LL n){    return rand()%(n-1)+1;}LL dec(LL x,LL y,LL p){    x-=y;    return x<0?x+p:x;}LL inc(LL x,LL y,LL p){    unsigned LL ret=(unsigned LL)x+y;    return ret>=p?ret-p:ret;}LL mul(LL x,LL y,LL p){    LL ret=0;    for (;y;y>>=1,x=inc(x,x,p))        if (y&1) ret=inc(ret,x,p);    return ret;}LL pow(LL x,LL y,LL p){    LL ret=1;    for (;y;y>>=1,x=mul(x,x,p))        if (y&1) ret=mul(ret,x,p);    return ret;}LL gcd(LL x,LL y){    return y?gcd(y,x%y):x;}/*inline bool check(LL n) {    if( n == 2 || n == 3 || n == 5 ) return 1;    if( n < 2 || !(n&1) || n % 3 == 0 || n % 5 == 0 ) return 0;    LL m = n - 1; int k = 0;    while( !(m & 1) ) m >>= 1, k++;    for (int i=1;i<=5;i++) {        LL x = pow(rand() % (n-1) + 1,m,n), y;        for (int j=1;j<=k;j++) {            y = mul(x,x,n);            if( y == 1 && x != 1 && x != n - 1 ) return 0;            x = y;        }        if( y != 1 ) return 0;    }    return 1;}*/inline int check(LL n){    /*for (int i=0;i<=3;i++)    {        if (n==prm[i]) return 1;        if (n%prm[i]==0) return 0;    }*/    /*if (n==2||n==3||n==5) return 1;    if (n<=1||(n&1)==0||n%2==0||n%3==0||n%5==0) return 0;*/    LL x=n-1,k=0,y,z;    while (!(x&1)) x>>=1,k++;    for (int i=1;i<=5;i++)    {        y=pow(Rand(n),x,n);        for (int j=1;j<=k;j++)        {            z=mul(y,y,n);            if (z==1&&y!=1&&y!=n-1) return 0;            y=z;        }        if (y!=1) return 0;    }    return 1;}LL solve(LL n){    if (check(n)) return n;    LL x=Rand(n),y,c=Rand(n),d;    y=x;    for (int i=1,k=1;;i++)    {        x=inc(mul(x,x,n),c,n);        d=gcd(dec(x,y,n),n);        if (d==n) return solve(n);        if (d>1) return max(solve(d),solve(n/d));        if (i==k) k<<=1,y=x;    }}int main(){    srand(321453);    int T;    LL n,ans;    scanf("%d",&T);    while (T--)    {        scanf("%lld",&n);        ans=solve(n);        if (ans==n) printf("Prime\n");        else printf("%lld\n",ans);    }}
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