大整数质因数分解模板

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LL Abs( LL a ){ return a<0?-a:a; }
LL Min( LL a , LL b ){ return a<b?a:b; }
LL Max( LL a , LL b ){ return a>b?a:b; }
LL Gcd( LL a , LL b ){ return b==0?a:Gcd( b , a%b ); }
LL arr[5] = { 2,3,5,233,331 };
LL Qmul( LL a , LL b , LL mod )
{
    LL res = 0;
    while ( b )
    {
        if ( b&1 )
            res = ( res+a )%mod;
        a = ( a+a )%mod;
        b = b>>1;
    }
    return res;
}
LL Qpow( LL a , LL b , LL mod )
{
    LL res = 1;
    while ( b )
    {
        if ( b&1 )
            res = Qmul( res , a , mod );
        a = Qmul( a , a , mod );
        b = b>>1;
    }
    return res;
}
bool Miller_Rabin( LL n )
{
    if ( n==2 ) return true;
    if ( n <2||n%2==0 ) return false;
    LL m = n-1,k = 0;
    while ( m%2==0 ) k++,m>>=1;
    for ( int i=0 ; i<5 ; i++ )
    {
        LL a = arr[i]%(n-1)+1;
        LL x = Qpow( a , m , n );
        for ( int j=1 ; j<=k ; j++ )
        {
            LL y = Qmul( x , x , n );
            if ( y==1&&x!=1&&x!=n-1 )
                return false;
            x = y;
        }
        if ( x!=1 ) return false;
    }
    return true;
}
LL fac[110],tol;
LL Pollard_rho( LL x , LL c )
{
    LL i=1,k=2;
    LL x0 = rand()%x;
    LL y0 = x0;
    while ( 1 )
    {
        i++;
        x0 = ( Qmul( x0 , x0 , x )+c )%x;
        LL d0 = Gcd( Abs( y0-x0 ) , x );
        if ( d0!=1&&d0!=x ) return d0;
        if ( y0==x0 ) return x;
        if ( i == k ) { y0=x0; k+=k; }
    }
}
void Findfac( LL n )
{
    if ( Miller_Rabin( n ) )
    {
        fac[tol++] = n;
        return;
    }
    LL p = n;
    while ( p>=n )
        p = Pollard_rho( p , rand()%(n-1)+1 );
    Findfac( p );
    Findfac( n/p );
}