HDU 1019

入门题，好多数的 LCM

#include <iostream>
#include <cstdio>
using namespace std;
#define LL long long
int t,n;
LL a[100000000];
LL ans;
LL gcd(LL a,LL b)
{
    if(a<b) swap(a,b);
    LL r=a%b;
    while(r)
    {
        a=b;
        b=r;
        r=a%b;
    }
    return b;
}
int main()
{
    scanf("%d",&t);
    while(t--)
    {
        scanf("%d",&n);
        for(int i=1;i<=n;i++) scanf("%lld",&a[i]);
        if(n==1){
             printf("%lld
",a[1]); continue;
        }
        ans=a[1]*a[2]/gcd(a[1],a[2]);
        for(int i=3;i<=n;i++)
        {
            ans=ans*a[i]/gcd(ans,a[i]);
        }
        printf("%lld
",ans);
    }
}//2016-04-22 17:12:29