#include <bits/stdc++.h>

using namespace std;

using ll = long long;

template <class T>
T smax(T & x, T y) {
    if (x < y) {
        x = y;
        return true;
    }
    return false;
}

template <class T>
T smin(T & x, T y) {
    if (x > y) {
        x = y;
        return true;
    }
    return false;
}

const int mod = 998244353;

int sum(int x, int y) {
    if (x + y >= mod) {
        return x + y - mod;
    }
    return x + y;
}

int diff(int x, int y) {
    if (x >= y) {
        return x - y;
    }
    return x - y + mod;
}

int mult(int x, int y) {
    return (int) ((x * 1LL * y) % mod);
}

int pow(int x, int p) {
    int ans = 1;
    while (p > 0) {
        if ((p & 1) == 1) {
            ans = mult(ans, x);
        }
        x = mult(x, x);
        p >>= 1;
    }
    return ans;
}

int inv(int x) {
    return pow(x, mod - 2);
}

void solve() {
    int a, b, c;
    cin >> a >> b >> c;
    int ans = 2 * a;
    if (c >= 2) {
        c -= 2;
        ans += 3 + 2 * b;
    }
    ans += c / 2 * 3;
    cout << ans << "\n";
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int t = 1;
//    cin >> t;
    while (t--) {
        solve();
    }
    cerr << clock() * 1.0 / CLOCKS_PER_SEC << "\n";
    return 0;
}