Problem Description
Alexandra has a little brother. He is new to programming. One day he is solving the following problem: Given an positive integer N, judge whether N is prime. The problem above is quite easy, so Alexandra gave him a new task: Given a positive integer N, find the minimal positive integer M, such that N/M is prime. If such M doesn't exist, output 0. Help him!
Input
There are multiple test cases (no more than 1,000). Each case contains only one positive integer N. N≤1,000,000,000. Number of cases with N>1,000,000 is no more than 100.
Output
For each case, output the requested M, or output 0 if no solution exists.
Sample Input
3
4
5
6
Sample Output
1
2
1
2
找出n的最大素因子，在用n除以最大素因子就行了。注意1无素因子，应该特殊考虑。