PKU 1811 - Prime Test (大素数测试和因数分解)
思路
两个模板
代码
#include <stack>
#include <cstdio>
#include <list>
#include <set>
#include <iostream>
#include <string>
#include <vector>
#include <queue>
#include <functional>
#include <cstring>
#include <algorithm>
#include <cctype>
#include <string>
#include <map>
#include <cmath>
using namespace std;
#define LL long long
#define ULL unsigned long long
#define SZ(x) (int)x.size()
#define Lowbit(x) ((x) & (-x))
#define MP(a, b) make_pair(a, b)
#define MS(arr, num) memset(arr, num, sizeof(arr))
#define PB push_back
#define X first
#define Y second
#define ROP freopen("input.txt", "r", stdin);
#define MID(a, b) (a + ((b - a) >> 1))
#define LC rt << 1, l, mid
#define RC rt << 1|1, mid + 1, r
#define LRT rt << 1
#define RRT rt << 1|1
#define BitCount(x) __builtin_popcount(x)
#define BitCountll(x) __builtin_popcountll(x)
#define LeftPos(x) 32 - __builtin_clz(x) - 1
#define LeftPosll(x) 64 - __builtin_clzll(x) - 1
const double PI = acos(-1.0);
const int INF = 0x3f3f3f3f;
const double eps = 1e-8;
const int MAXN = 1e6 + 10;
const int MOD = 1000007;
const int dir[][2] = { {1, 0}, {0, 1} };
int cases = 0;
typedef pair<int, int> pii;
typedef vector<int>::iterator viti;
typedef vector<pii>::iterator vitii;
set<LL> fac;
LL multi(LL a, LL b, LL m)
{
LL ans = 0;
a %= m;
while(b)
{
if(b & 1)
{
ans = (ans + a) % m;
b--;
}
b >>= 1;
a = (a + a) % m;
}
return ans;
}
LL quick_mod(LL a, LL b, LL m)
{
LL ans = 1;
a %= m;
while(b)
{
if(b & 1)
{
ans = multi(ans, a, m);
b--;
}
b >>= 1;
a = multi(a, a, m);
}
return ans;
}
bool Miller_Rabin(LL n)
{
if(n == 2) return true;
if(n < 2 || !(n & 1)) return false;
LL m = n - 1;
int k = 0;
while((m & 1) == 0)
{
k++;
m >>= 1;
}
for(int i=0; i<10; i++)
{
LL a = rand() % (n - 1) + 1;
LL x = quick_mod(a, m, n);
LL y = 0;
for(int j=0; j<k; j++)
{
y = multi(x, x, n);
if(y == 1 && x != 1 && x != n - 1) return false;
x = y;
}
if(y != 1) return false;
}
return true;
}
LL pollard_rho(LL n, LL c)
{
LL i = 1, k = 2;
LL x = rand() % (n - 1) + 1;
LL y = x;
while(true)
{
i++;
x = (multi(x, x, n) + c) % n;
LL d = __gcd((y - x + n) % n, n);
if(1 < d && d < n) return d;
if(y == x) return n;
if(i == k)
{
y = x;
k <<= 1;
}
}
}
bool Find(LL n, int c) //如果是素数返回false
{
if(n == 1) return false;
if(Miller_Rabin(n))
{
fac.insert(n);
return false;
}
LL p = n;
LL k = c;
while(p >= n) p = pollard_rho(p, c--);
Find(p, k);
Find(n / p, k);
return true;
}
int main()
{
LL n;
int T;
scanf("%d", &T);
while(T--)
{
scanf("%lld", &n);
fac.clear();
if (Find(n, 120)) printf("%d\n", *fac.begin());
else puts("Prime");
}
return 0;
}