#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b, c;
  cin >> a >> b >> c;
  int r = min(a / 3, min(b / 2, c / 2));
  a -= 3 * r;
  b -= 2 * r;
  c -= 2 * r;
  int ans = 7 * r;
  int cnt1 = 0;
  for (int i = 0; i < 14; i++) {
    int a1 = a, b1 = b, c1 = c, cnt = 0;
    for (int j = i; j < 14; j++) {
      if (j == 0 || j == 3 || j == 6 || j == 7 || j == 10 || j == 13) a1--;
      if (j == 1 || j == 5 || j == 8 || j == 12) b1--;
      if (j == 2 || j == 4 || j == 9 || j == 11) c1--;
      if (a1 < 0 || b1 < 0 || c1 < 0) {
        cnt1 = max(cnt1, cnt);
        break;
      }
      cnt++;
    }
  }
  cout << ans + cnt1;
}
