#include <iostream>
#include <cstdio>
#include <cmath>
#include <cstring>
#include <algorithm>
#include <string>
#include <vector>
#include <stack>
#include <queue>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <sstream>
#include <complex>
#include <ctime>
#include <cassert>
#include <functional>

using namespace std;

typedef long long ll;
typedef vector<int> VI;
typedef pair<int,int> PII;

#define REP(i,s,t) for(int i=(s);i<(t);i++)
#define FILL(x,v) memset(x,v,sizeof(x))

int main() {
  int g, r;
  cin >> g >> r;
  r = min(r, g);
  int ans = r * 10;
  g -= r;
  ans += g / 3 * 10;
  g %= 3;
  ans += g / 2 * 3;
  g %= 2;
  ans += g;
  cout << ans << endl;
  return 0;
}