#include <bits/stdc++.h>
#define rep(i,n) for (int i = 0; i < (n); i ++)
using namespace std;
typedef long long ll;
typedef pair<ll,ll> PL;
typedef pair<int,int> P;
const int INF = 1e9;
const ll MOD = 1e9 + 7;

int main() {
    int A,B; cin >> A >> B;
    cout << min(A,B)*2 << endl;
}