Smallest multiple

problem 5：Smallest multiple

题意：求最小的正数，使得其可以被1-20整除

代码如下：

 #ifndef PRO5_H_INCLUDED
 #define PRO5_H_INCLUDED

 #include "prime.h"

 namespace pro5{
     long long solve(){
         ;
         ;i<=;++i)
             ans=lcm(ans,i);
         return ans;
     }
 }

 #endif // PRO5_H_INCLUDED

有关函数：

 long long gcd(long a,long b){
     ?a:gcd(b,a%b);
 }

 long long lcm(long a,long b){
     return a/gcd(a,b)*b;
 }