K - Least Common Multiple

Time Limit:1000MS     Memory Limit:32768KB     64bit IO Format:%I64d & %I64u

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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

 

这道题就是要求多个数的最小公倍数；

思路很简单，就是每两个数求他们的最小公倍数，然后用求出的最小公倍数与下一个数

 #include<stdio.h>
 int gcd(int a,int b)
 {
     if(b==) return a;
     return gcd(b,a%b);
 }
 int main()
 {
     int t;
     int n,a,b,i;
     int cnt;
     scanf("%d",&t);
     while(t--)
     {
         scanf("%d",&n);
         cnt=a=;
         for(i=;i<=n;i++)
         {
             scanf("%d",&b);
             cnt=a/gcd(a,b)*b;
             a=cnt;
         }
         printf("%d\n",cnt);
     }
     return ;
 }