HDU2710 Max Factor

Description

To improve the organization of his farm, Farmer John labels each of his N (1 <= N <= 5,000) cows with a distinct serial number in the range 1..20,000. Unfortunately, he is unaware that the cows interpret some serial numbers as better than others. In particular, a cow whose serial number has the highest prime factor enjoys the highest social standing among all the other cows. 

(Recall that a prime number is just a number that has no divisors except for 1 and itself. The number 7 is prime while the number 6, being divisible by 2 and 3, is not). 

Given a set of N (1 <= N <= 5,000) serial numbers in the range 1..20,000, determine the one that has the largest prime factor. 

Input

* Line 1: A single integer, N 

* Lines 2..N+1: The serial numbers to be tested, one per line

Output

* Line 1: The integer with the largest prime factor. If there are more than one, output the one that appears earliest in the input file.

Sample Input

4
36
38
40
42

Sample Output

38

题目大意:就是求所给数的素因子最大的数,如果存在多个这样的数,那么输出他们中最小的就可以了:


#include
#include
#include
using namespace std;
const int M=200005;
int prime[M],pe[M];
void Init()
{
	memset(prime,0,sizeof(prime));
	for(int i=2;i>N)
	{	
		int pmax=-1;
		int res;
		for(int i=0;i>a;
			int temp=solve(a);
//			cout<<"temp="<


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