Code

#include <bits/stdc++.h>

using namespace std;

#define __File(name) if (fopen(name".inp", "r")) freopen(name".inp", "r", stdin), freopen(name".out", "w", stdout);
#define ll long long
#define pb push_back
#define fi first
#define se second
#define NAME "zukako"

ll a, b, c;
signed main() {
    __File(NAME);
    ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    cin >> a >> b >> c;
    while (a > 0 && b > 0) {
        c++;
        --a; --b;
    } 
    while (a >= 3) {
        c++;
        a -= 3;
    }
    cout << c;
    return 0;
}