#include <bits/stdc++.h>

using namespace std;

#define LOG(...) fprintf(stderr,__VA_ARGS__)
//#define LOG(...)
#define FOR(i,a,b) for(int i=(int)(a);i<(int)(b);++i)
#define REP(i,n) for(int i=0;i<(int)(n);++i)
#define ALL(a) (a).begin(),(a).end()
#define RALL(a) (a).rbegin(),(a).rend()
#define EXIST(s,e) ((s).find(e)!=(s).end())
#define SORT(c) sort(ALL(c))
#define RSORT(c) sort(RALL(c))

typedef long long ll;
typedef unsigned long long ull;
typedef vector<bool> vb;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<vb> vvb;
typedef vector<vi> vvi;
typedef vector<vll> vvll;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

int main() {
    int r, g, b;
    cin >> r >> g >> b;

    int res = 0;

    int mi = min(r, min(g, b));
    r -= mi;
    g -= mi;
    b -= mi;
    res += mi;

    while (1) {
        int n = 0;
        if (r > 2) n += r/2;
        if (g > 2) n += g/2;
        if (b > 2) n += b/2;

        int z = (r==0)+(g==0)+(b==0);
        if (z > n) {
            break;
        }

        int ma = max(r, max(g, b));
        if (r == ma) {
            r -= 2 * z;
            r--;
            if (g != 0) g--;
            if (b != 0) b--;
        } else if (g == ma) {
            g -= 2 * z;
            g--;
            if (r != 0) r--;
            if (b != 0) b--;
        } else if (b == ma) {
            b -= 2 * z;
            b--;
            if (r != 0) r--;
            if (g != 0) g--;
        }
        res++;
    }

    cout << res << endl;
}