#include <bits/stdc++.h>
#define rep(i, j) for (int i = 0; i < (int)(j); ++i)
#define rep1(i, j) for (int i = 1; i < (int)(j); ++i)
#define all(v) (v).begin(), (v).end()

using namespace std;
using ll = long long;
using ld = long double;

signed main()
{
  int a, b; cin >> a >> b;
  cout << min(a, b) * 2 << endl;
}