#include <iostream>
#include <algorithm>
using namespace std;
int main()
{
    int r, g, b;
    while (cin>>r>>g>>b) {
        int res=min({r, g, b});
        bool changed=true;
        while (changed) {
            changed=false;
            auto x=minmax({r, g, b});
            int s=r+g+b;
            r=x.first, b=x.second, g=s-(r+b);
            if (b>=2) { b-=2; r++; changed=true; }
            res=max(res, min({r, g, b}));
        }
        cout<<res<<endl;
    }
}