HDU-1019 Least Common Multiple

Description

The least common multiple (LCM) of a set of positive integers is the smallest positive integer which is divisible by all the numbers in the set. For example, the LCM of 5, 7 and 15 is 105.

 

Input

Input will consist of multiple problem instances. The first line of the input will contain a single integer indicating the number of problem instances. Each instance will consist of a single line of the form m n1 n2 n3 ... nm where m is the number of integers in the set and n1 ... nm are the integers. All integers will be positive and lie within the range of a 32-bit integer.

 

Output

For each problem instance, output a single line containing the corresponding LCM. All results will lie in the range of a 32-bit integer.

 

Sample Input

2

3 5 7 15

6 4 10296 936 1287 792 1

 

Sample Output

105

10296

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最小公倍数等于两数相乘除以最大公因数。（欧几里得算法）

#include <iostream>
#include <cmath>
#include <algorithm>
using namespace std;

int main(void)
{
    int t;
    long func(long, long);
    
    cin >> t;
    while(t--)
    {
        long long q = 1;
        int m;
        long num;

        
        cin >> m;
        while(m--)
        {
            cin >> num;
            q = num/func(q, num)*q;
        }
        cout << q << endl;
        
    }
    
    return 0;
}


long func(long a, long b)
{
    long q = max(a, b);
    long p = a+b-q;
    
    while(q%p!=0)
    {
        p = q+p;
        q = p-q;
        p = p-q;
        p = p%q;
    }
    return p;
}