#include <iostream>
#include <stdio.h>
#include <string>
#include <vector>
#include <cmath>
#include <algorithm>
#define MP make_pair
using ll = long long;
using namespace std;

int main()
{
  int n;
  cin >> n;
  vector<vector<ll> >H(n, vector<ll>(2));
  for(int i=0; i < n; i++){
    cin >> H[i][0];
    cin >> H[i][1];
  }
  vector<ll>D(n);
  for(int i=0; i < n; i++){
    D[i] = H[i][0] + H[i][1];
    //cout << D[i] << endl;
  }
  sort(D.begin(), D.end());
  ll ans = 0;
  vector<ll>S(n);
  S[0] = D[0];
  vector<ll>B(n);
  B[0] = D[n-1];
  for(int i=1; i < n; i++)
    S[i] = S[0] + D[i];
  for(int i=1; i < n; i++)
    B[i] = B[0] + D[n-i];
  ll sum=0;
  for(int i=0; i < n; i++)
    sum += H[i][0];
  int k;
  ll min1 = 1000000000;
  ll min2 = 1000000000;
  int mink1, mink2;
  for(k=1; k < n; k++){
    if(abs(sum - S[k]) <= min1){
      min1 = sum - S[k];
      mink1 = k;
    }
  }
  for(k=1; k < n; k++){
    if(abs(sum - B[k]) <= min2){
      min2 = abs(sum - B[k]);
      mink2 = k;
    }
  }
  if(n >= 2){
  if(min1 < min2)
    cout << abs(sum-S[mink1]) << endl;
  else
    cout << abs(sum-B[mink2]) << endl;
  }else{
    if(H[0][0] < H[0][1])
      cout << H[0][0] << endl;
    else
      cout << H[0][1] << endl;
  }
    return 0;
}