一次性AC，用时8分钟

#include<iostream>
using namespace std;
int lcm(int n1,int n2)
{
    int s;
    if(n1>n2)
        s=n1;
    else
        s=n2;
    while(s%n1!=0 || s%n2!=0)
        s++;
    return s;
}
int main()
{
//  freopen("xxx.in","r",stdin);
//  freopen("yyy.out","w",stdout);
    int n1,n2;
    cin >> n1 >> n2;
    cout << lcm(n1,n2); 
//  fclose(stdin);
//  fclose(stdout);
    return 0;
 }