#include <iostream>
 
using namespace std;
 
int gcd(int u, int v)
{
   if (v==0)
     return u;
   else
     return gcd(v, u%v);
}
 
int lcm(int u, int v)
{
  // least common multiplier is the product of the two
  // numbers divided by the GCD (GCD would otherwise
  // be included twice, which is unnecessary); note that
  // I first divide one number by GCD, so that we don't
  // end up with a too large of a number when it is not
  // necessary
 
  u /= gcd(u,v);
 
  return u*v;
} 
 
int main()
{
  int i;
  int result = 1;
 
  // number that can be divided by 1 through 2 is
  // the least common multiplier of all the numbers,
  // which can be computed one number at a time
 
  for (i=2; i<=20; i++)
    result = lcm(result, i);
 
  cout << result << endl;
 
  return 0;
}

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