51nod1419 lcm，规律

#include <iostream>
#include <cstdio>
#include <string>
#include <cstring>
#include <fstream>
#include <algorithm>
#include <cmath>
#include <queue>
#include <stack>
#include <vector>
#include <map>
#include <set>
#include <iomanip>

using namespace std;
#pragma comment(linker, "/STACK:102400000,102400000")
#define maxn 100010
#define MOD 1000000007
#define mem(a , b) memset(a , b , sizeof(a))
#define LL long long
#define INF 100000000

int main()
{
LL n;
while(scanf("%lld" , &n) != EOF)
{
if(n < 3) printf("%d\n" , n);
else if(n % 2) printf("%lld\n" , n* (n-1) *(n-2));
else if(n % 3) printf("%lld\n" , n* (n-1) *(n-3));
else printf("%lld\n" , (n-2)* (n-1) *(n-3));
}
return 0;
}