#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b, c;
  scanf("%d%d%d", &a, &b, &c);
  int aweek = a / 3;
  int bweek = b / 2;
  int cweek = c / 2;
  int ans = min(aweek, min(bweek, cweek));
  ans -= 2;
  ans = max(ans, 0);
  a -= ans * 3;
  b -= ans * 2;
  c -= ans * 2;
  ans *= 7;
  int tmp = 0;
  for (int i = 1; i <= 7; i++) {
    int tmpa = a, tmpb = b, tmpc = c;
    int total = 0;
    int cnt = i;
    while (true) {
      if (cnt == 1 || cnt == 4 || cnt == 7) {
        if (tmpa > 0)
          tmpa--;
        else
          break;
      } else if (cnt == 2 || cnt == 6) {
        if (tmpb > 0)
          tmpb--;
        else
          break;
      } else {
        if (tmpc > 0)
          tmpc--;
        else
          break;
      }
      total++;
      cnt++;
      if (cnt == 8) cnt = 1;
    }
    tmp = max(tmp, total);
  }
  printf("%d", ans + tmp);
  return 0;
}
