题目
July 2, 2021 · View on GitHub
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
参考答案
#include <stdio.h>
#include <stdlib.h>
#include <iostream>
#include <memory.h>
#define MAX 10001
using namespace std;
long long int gcd(long long int x,long long int y)
{
return y == 0? x : gcd(y,x%y);
}
int main(void)
{
int num[MAX];
int ncases,n;
scanf("%d",&ncases);
while( ncases -- )
{
scanf("%d",&n);
for(int i=0; i<n; i++)
scanf("%d",&num[i]);
if( n == 1 )
{
printf("%d\n",num[0]);
continue;
}
int temp = gcd(num[0],num[1]);
if(temp == 0 )
{
printf("%d\n",temp);
continue;
}
temp = num[0]/temp*num[1];
for(int i=2; i<n; i++)
{
int x = gcd(temp,num[i]);
if( x == 0 )
{
temp = 0;
break;
}
temp = temp/x*num[i];
}
printf("%d\n",temp);
}
return 0;
}