#include<bits/stdc++.h>
using namespace std;
#define rep(i,a,b) for(ll i=(ll)(a);i<(ll)(b);i++)
using ll = long long;
using ld = long double;
const ll INF = (1ll<<61) - 1;
#define all(p) p.begin(),p.end()
template<class T> bool chmin(T &a,T b){
    if(a>b){
        a=b;
        return true;
    }
    return false;
}


int main(){
    int N;
    cin>>N;
    vector<int> A(N),B(N);
    rep(i,0,N) cin>>A[i]>>B[i];
    if(N==1){
        cout<<min(A[0],B[0])<<"\n";
    }
    auto f=[&](auto self,int l,int r,vector<pair<int,int>> &v) -> void {
        if(l==r) return;
        vector<pair<int,int>> n_v;
        int inda=0,indb=0;
        while(inda!=v.size()){
            if(indb==v.size()||v[inda].first+A[l]<v[indb].first){
                n_v.push_back({v[inda].first+A[l],v[inda].second});
                inda++;
            }
            else{
                n_v.push_back({v[indb].first,v[indb].second+B[l]});
                indb++;
            }
        }
        swap(n_v,v);
        self(self,l+1,r,v);
    };
    vector<pair<int,int>> X={{0,0}},Y={{0,0}};
    f(f,0,N/2,X);
    f(f,N/2,N,Y);
    rep(i,1,X.size()) chmin(X[i].second,X[i-1].second);
    rep(i,1,Y.size()) chmin(Y[i].second,Y[i-1].second);
    reverse(all(X));
    int indX=0,indY=0;
    int ans=max(X[0].first+Y[0].first,X[0].second+Y[0].second);
    while(indX+1!=X.size()&&indY+1!=Y.size()){
        if(indX+1==X.size()) indY++;
        else if(indY+1==Y.size()) indX++;
        else if(X[indX].first+Y[indY].first<X[indX].second+Y[indY].second){
            indY++;
        }
        else indX++;
        chmin(ans,max(X[indX].first+Y[indY].first,X[indX].second+Y[indY].second));
    }
    cout<<ans<<"\n";
}