hdu 2421 Deciphering Password（约数个数问题）

#include <stdio.h>
#include <iostream>
#include <map>
#include <set>
#include <bitset>
#include <list>
#include <stack>
#include <vector>
#include <math.h>
#include <string.h>
#include <queue>
#include <string>
#include <stdlib.h>
#include <algorithm>
//#define LL __int64
#define LL long long
#define eps 1e-9
const double PI = acos(-1.0);
using namespace std;

const int maxn = 1000010;
const int mod = 10007;

LL A,B;
int prime[maxn];
bool flag[maxn];
LL facCnt[1010]; //由于数组开的太大，每次都须要初始化，导致TLE了几次。
int cnt;

void getPrime()
{
    memset(flag,false,sizeof(flag));
    prime[0] = 0;
    for(int i = 2; i < maxn; i++)
    {
        if(flag[i] == false)
            prime[++prime[0]] = i;
        for(int j = 1; j <= prime[0] && prime[j]*i < maxn; j++)
        {
            flag[prime[j]*i] = true;
            if(i % prime[j] == 0)
                break;
        }
    }
}

void getFac()
{
    LL tmp = A;
    cnt = 0;
    memset(facCnt,0,sizeof(facCnt));
    for(int i = 1; i <= prime[0]&&prime[i]*prime[i] <= tmp; i++)
    {
        if(tmp % prime[i] == 0)
        {
            while(tmp%prime[i]==0)
            {
                facCnt[cnt]++;
                tmp /= prime[i];
            }
            cnt++;
        }
        if(tmp == 1)
            break;
    }
    if(tmp > 1)
    {
        facCnt[cnt++] = 1;
    }
}

int main()
{
    getPrime();
    int item = 0;
    while(~scanf("%I64d %I64d",&A,&B))
    {
        getFac();
        LL ans = 1;
        for(int i = 0; i < cnt; i++)
        {
            LL s = (((facCnt[i]*B+1)*(facCnt[i]*B+2))/2 )%mod;
            s = (s*s)%mod;
            ans = (ans*s)%mod;
        }
        printf("Case %d: %I64d\n",++item,ans);
    }
}