uva 11752 - The Super Powers

这个题   任意一个数，他的幂只要不是质数则可以分解成两个数的乘   判断有没有溺出  i×i  则用最大的那个数 Max/i < i 吗 

#include<iostream>
#include<cstring>
#include<algorithm>
#include<cmath>
#include<stdio.h>
#include<set>
using namespace std;
typedef  unsigned long long ll;
const ll Max = 0xffffffffffffffffLL;//18446744073709551615;
set<ll>s;
bool work( int num ){
    for( int i = 2; i <= sqrt(num); i++ )
    if( !(num%i) ) return false;
    return true;
}
int main( )
{
    //freopen("out1.txt","w",stdout);
    s.clear(); s.insert(1); set<ll>::iterator it;
    for( ll i = 2; i <= (1<<22); i++ )
    {
        ll ans = i*i;  int num = 2;
        while( 1 ){
            if( Max/ans < i )break;
            ans = ans*(i); num++;
            if( !work(num) )s.insert(ans);
        }
    }
    for( it = s.begin(); it != s.end(); it++ )
    printf("%llu\n",*it);
    return 0;
}