Smallest Multiple

Problem

Problem Link

$2520$ is the smallest number that can be divided by each of the numbers from $1$ to $10$ without any remainder.

What is the smallest positive number that is evenly divisible by all of the numbers from $1$ to $20$?

Solution

CodeCPP fileDownload

#include <iostream>
 
inline int gcd(int a, int b) { return b ? gcd(b, a % b) : a; }
inline int lcm(int a, int b) { return a / gcd(a, b) * b; }
 
int main(void) {
  int ans = 1;
  for (int i = 1; i <= 20; ++i) {
    ans = lcm(ans, i);
  }
  std::cout << ans << std::endl;
  return 0;
}