Intelligent Factorial Factorization LightOJ

就是暴力嘛。。。很水的一个题。。。

不好意思交都。。。

#include <iostream>
#include <cstdio>
#include <sstream>
#include <cstring>
#include <map>
#include <set>
#include <vector>
#include <stack>
#include <queue>
#include <algorithm>
#include <cmath>
#define MOD 2018
#define LL long long
#define ULL unsigned long long
#define Pair pair<int, int>
#define mem(a, b) memset(a, b, sizeof(a))
#define _  ios_base::sync_with_stdio(0),cin.tie(0)
//freopen("1.txt", "r", stdin);
using namespace std;
const int maxn = 10010, INF = 0x7fffffff;
int primes[maxn], base[maxn], mi[maxn];
int vis[maxn];
int ans = 0;
set<int> s;
void init()
{
    mem(vis, 0);
    for(int i=2; i<maxn; i++)
    {
        if(vis[i]) continue;
        primes[ans++] = i;
        for(LL j=(LL)i*i; j<maxn; j+=i)
            vis[j] = 1;
    }
}

int main()
{
    init();
    int T, kase = 0;
    scanf("%d",&T);
    while(T--)
    {
        s.clear();
        mem(base, 0);

        int n;
        scanf("%d",&n);
        for(int i=2; i<=n; i++)
        {
            int temp = i;
            for(int j=0; j<ans && primes[j] * primes[j] <= temp; j++)
            {
                while(temp % primes[j] == 0)
                {
                    temp /= primes[j];
                    base[primes[j]]++;
                }
                if(base[primes[j]] > 0)
                {
                    s.insert(primes[j]);
                }
            }
            if(temp > 1)
            {
                base[temp]++;
                s.insert(temp);
            }
        }
        printf("Case %d: %d = ",++kase, n);
        int cnt = 0;
        for(set<int>::iterator it=s.begin(); it!=s.end(); it++)
        {
            if(cnt == 0)
                printf("%d (%d)",*it, base[*it]);
            else
                printf(" * %d (%d)",*it, base[*it]);
            cnt++;
        }
        printf("
");

    }

    return 0;
}