#line 2 "cpplib/util/template.hpp"
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("avx2")
#include<bits/stdc++.h>
using namespace std;
#line 1 "cpplib/util/ioutil.hpp"
// template <class Head,class... Args>
// std::ostream& output(std::ostream& out,const Head& head,const Args&... args){
//     out>>head;
//     return output(head,args...);
// }
// template <class Head>
// std::ostream& output(std::ostream& out,const Head& head){
//     out>>head;
//     return out;
// }

template<typename T,typename E>
std::ostream& operator<<(std::ostream& out,std::pair<T,E>v){
    out<<"("<<v.first<<","<<v.second<<")";return out;
}

// template <class... Args>
// ostream& operator<<(ostream& out,std::tuple<Args...>v){
//     std::apply(output,v);
//     return out;
// }
#line 8 "cpplib/util/template.hpp"
struct __INIT__{__INIT__(){cin.tie(0);ios::sync_with_stdio(false);cout<<fixed<<setprecision(15);}}__INIT__;
typedef long long lint;
constexpr long long INF=1LL<<60;
constexpr int IINF=1<<30;
constexpr double EPS=1e-10;
#define endl '\n';
typedef vector<lint> vec;
typedef vector<vector<lint>> mat;
typedef vector<vector<vector<lint>>> mat3;
typedef vector<string> svec;
typedef vector<vector<string>> smat;
template<typename T>using V=vector<T>;
template<typename T>using VV=V<V<T>>;
template<typename T>inline void output(T t){bool f=0;for(auto i:t){cout<<(f?" ":"")<<i;f=1;}cout<<endl;}
template<typename T>inline void output2(T t){for(auto i:t)output(i);}
template<typename T>inline void debug(T t){bool f=0;for(auto i:t){cerr<<(f?" ":"")<<i;f=1;}cerr<<endl;}
template<typename T>inline void debug2(T t){for(auto i:t)debug(i);}
#define loop(n) for(long long _=0;_<(long long)(n);++_)
#define _overload4(_1,_2,_3,_4,name,...) name
#define __rep(i,a) repi(i,0,a,1)
#define _rep(i,a,b) repi(i,a,b,1)
#define repi(i,a,b,c) for(long long i=(long long)(a);i<(long long)(b);i+=c)
#define rep(...) _overload4(__VA_ARGS__,repi,_rep,__rep)(__VA_ARGS__)
#define _overload3_rev(_1,_2,_3,name,...) name
#define _rep_rev(i,a) repi_rev(i,0,a)
#define repi_rev(i,a,b) for(long long i=(long long)(b)-1;i>=(long long)(a);--i)
#define rrep(...) _overload3_rev(__VA_ARGS__,repi_rev,_rep_rev)(__VA_ARGS__)

#define all(n) begin(n),end(n)
template<typename T,typename E>bool chmin(T& s,const E& t){bool res=s>t;s=min<T>(s,t);return res;}
template<typename T,typename E>bool chmax(T& s,const E& t){bool res=s<t;s=max<T>(s,t);return res;}
const vector<lint> dx={1,0,-1,0,1,1,-1,-1};
const vector<lint> dy={0,1,0,-1,1,-1,1,-1};
#define SUM(v) accumulate(all(v),0LL)
#if __cplusplus>=201703L
    template<typename T,typename ...Args>auto make_vector(T x,int arg,Args ...args){if constexpr(sizeof...(args)==0)return vector<T>(arg,x);else return vector(arg,make_vector<T>(x,args...));}
#endif
#define extrep(v,...) for(auto v:__MAKE_MAT__({__VA_ARGS__}))
#define bit(n,a) ((n>>a)&1)
vector<vector<long long>> __MAKE_MAT__(vector<long long> v){if(v.empty())return vector<vector<long long>>(1,vector<long long>());long long n=v.back();v.pop_back();vector<vector<long long>> ret;vector<vector<long long>> tmp=__MAKE_MAT__(v);for(auto e:tmp)for(long long i=0;i<n;++i){ret.push_back(e);ret.back().push_back(i);}return ret;}
using graph=vector<vector<int>>;
template<typename T>using graph_w=vector<vector<pair<int,T>>>;

#if __cplusplus>=201703L
    constexpr inline long long powll(long long a,long long b){long long res=1;while(b--)res*=a;return res;}
#endif

template<typename T,typename E>pair<T,E>& operator+=(pair<T,E>&s,const pair<T,E>&t){s.first+=t.first;s.second+=t.second;return s;}
template<typename T,typename E>pair<T,E>& operator-=(pair<T,E>&s,const pair<T,E>&t){s.first-=t.first;s.second-=t.second;return s;}
template<typename T,typename E>pair<T,E> operator+(const pair<T,E>&s,const pair<T,E>&t){auto res=s;return res+=t;}
template<typename T,typename E>pair<T,E> operator-(const pair<T,E>&s,const pair<T,E>&t){auto res=s;return res-=t;}
#define BEGIN_STACK_EXTEND(size) void * stack_extend_memory_ = malloc(size);void * stack_extend_origin_memory_;char * stack_extend_dummy_memory_ = (char*)alloca((1+(int)(((long long)stack_extend_memory_)&127))*16);*stack_extend_dummy_memory_ = 0;asm volatile("mov %%rsp, %%rbx\nmov %%rax, %%rsp":"=b"(stack_extend_origin_memory_):"a"((char*)stack_extend_memory_+(size)-1024));
#define END_STACK_EXTEND asm volatile("mov %%rax, %%rsp"::"a"(stack_extend_origin_memory_));free(stack_extend_memory_);
#line 2 "main.cpp"

template<typename T>
class AVL_set{
	struct node;
	using np=node*;
    struct node{
        T val;
        int cnt=1;
        int dep=0;
        np ch[2]={nullptr,nullptr};
        node(T val):val(val){}
    };
    np root=nullptr;
    inline int count(np t){return t?t->cnt:0;}
    inline int depth(np t){return t?t->dep:0;}
    inline np update(np& t,bool f=1){
		if(!t)return t;
        t->cnt=count(t->ch[0])+1+count(t->ch[1]);
        t->dep=max(depth(t->ch[0]),depth(t->ch[1]))+1;
        if(f&&abs(depth(t->ch[0])-depth(t->ch[1]))==2){
			rebuild(t,depth(t->ch[0])<depth(t->ch[1]));
		}
        return t;
    }

    public:
	AVL_set(){}
    inline void insert(T val){insert(val,root);}
    inline void erase(T val){erase(val,root);}
    inline int lower_bound(T val){return lower_bound(val,root);}
	inline int upper_bound(T val){return upper_bound(val,root);}
	inline int size(){return count(root);}
	inline T find_by_order(int idx){assert(0<=idx&&idx<size());return find_by_order(idx,root);}
	inline T operator[](int idx){return find_by_order(idx);}
    private:
    void insert(T val,np& t){
        if(!t)t=new node(val);
        else if(val==t->val)return;
        else if(val<t->val)insert(val,t->ch[0]);
        else if(val>t->val)insert(val,t->ch[1]);
        update(t);
    }
    void erase(T val,np& t){
        if(!t)return;
        else if(val==t->val){
			if(!t->ch[0]||!t->ch[1])t=t->ch[0]?t->ch[0]:t->ch[1];
			else move_down(t->ch[0],t);
		}
        else if(val<t->val)erase(val,t->ch[0]);
        else if(val>t->val)erase(val,t->ch[1]);
		update(t);
    }
	void move_down(np& t,np& p){
		if(t->ch[1])move_down(t->ch[1],p);
		else p->val=t->val,t=t->ch[0];
		update(t);
	}
    int lower_bound(T val,np t){
        if(!t)return 0;
        if(val==t->val)return count(t->ch[0]);
        if(val<t->val)return lower_bound(val,t->ch[0]);
        else return count(t->ch[0])+1+lower_bound(val,t->ch[1]);
    }
	int upper_bound(T val,np t){
        if(!t)return 0;
        if(val<t->val)return upper_bound(val,t->ch[0]);
        else return count(t->ch[0])+1+upper_bound(val,t->ch[1]);
    }
	T find_by_order(int idx,np t){
		if(idx==count(t->ch[0]))return t->val;
		else if(idx<count(t->ch[0]))return find_by_order(idx,t->ch[0]);
		else return find_by_order(idx-count(t->ch[0])-1,t->ch[1]);
	}
	np rot(np t){
		int b=depth(t->ch[0])<depth(t->ch[1]);
		if(depth(t->ch[0])==depth(t->ch[1]))return t;
		np s=t->ch[b];
		t->ch[b]=s->ch[1-b];
		s->ch[1-b]=t;
		update(t,0);update(s,0);
		return s;
	}
    void rebuild(np& t,int b){
		if(t->ch[b]&&depth(t->ch[b]->ch[b])<depth(t->ch[b]->ch[1-b])){
			t->ch[b]=rot(t->ch[b]);
		}
		t=rot(update(t,0));
    }
};

int main(){
	lint x,y,z;
	cin>>x>>y>>z;
	lint ans=0;
	rep(i,z+1){
		chmax(ans,min(x+i,y+z-i));
	}
	cout<<ans<<endl;
}


// int main(){
//     int n,k;
//     cin>>n>>k;
//     vec v(n);
//     rep(i,n)cin>>v[i];
//     sort(all(v));
//     auto get=[&](int to,int from){
//         return (to-from)*v[to-1];
//     };
//     cout<<alien_dp<lint,decltype(get)>(n, k,INF, get)<<endl;
// }

// map<lint,lint> table(lint n){
//     lint l = 1,r;
//     map<lint,lint>res;
//     res[1]=n;
//     while(l <= n){
//         r = n / (n / l) + 1;
//         res[r]=n/r-n/l;
//         l = r;
//     }
//     return res;
// }

// map<lint,lint> merge(map<lint,lint>s,map<lint,lint>t){
//     map<lint,lint>res;
//     for(auto [p,q]:s)res[p]+=q;
//     for(auto [p,q]:t)res[p]-=q;
//     lint pre=0;
//     for(auto [p,q]:res){
//         res[p]+=pre;
//         pre=res[p];
//     }
//     return res;
// }

// map<lint,mint>get_mebius(lint n){
//     Dirichlet<mint>::resize(n);
//     auto dir=Dirichlet<mint>::mebius();
//     vector<mint>suma=dir.a;
//     rep(i,suma.size()-1)suma[i+1]+=suma[i];
//     auto get=[&](long long k){return (k<=Dirichlet<mint>::K?suma[k]:dir.A[n/k]);};
//     lint l = 1,r;
//     map<lint,mint>res;
//     // debug(suma);
//     res[1]=get(1);
//     while(l <= n){
//         r = n / (n / l) + 1;
//         res[r]=get(r);
//         l = r;
//     }
//     return res;
// }

// map<lint,mint> merge2(map<lint,mint>s,map<lint,mint>t){
//     map<lint,mint>res;
//     for(auto [p,q]:s)res[p]=q;
//     for(auto [p,q]:t)res[p]=q;
//     return res;
// }


// void solve(){
//     lint l,r;
//     cin>>l>>r;
//     vec v(r+1);
//     auto tb=merge(table(r),table(l-1));
//     lint pre=0;
//     lint preq=0;
//     auto res=merge2(get_mebius(r),l!=1?get_mebius(l-1):map<lint,mint>());
//     mint ans=0;
//     for(auto [p,q]:tb){
//         // cerr<<p<<" "<<q<<endl;
//         cerr<<p<<" "<<q<<" "<<res[p]<<endl;
//         ans+=mint(2).pow(preq)*(res[pre]-res[p]);
//         pre=p;
//         preq=q;
//     }
//     cout<<ans<<endl;
// }
// int main(){
//     solve();
// }
// int main(){
//     lint t;
//     cin>>t;
//     while(t--)solve();
// }