// Source: https://usaco.guide/general/io

#include <bits/stdc++.h>
using namespace std;

int main() {
    int n;cin>>n;
    vector<int> v(n);
    vector<int> tav(100002),erk(100002);
    for(int i = 0;i<n;i++){
        int a,b;cin>>a>>b;
        erk[a]++;
        tav[b+1]++;
    }
    for(int i = 1;i<100001;i++){
        erk[i]+=erk[i-1];
        tav[i]+=tav[i-1];
    }
    int mx=INT_MAX,indi=0;
    int j = 1;
    for(int i = 1;i<=100000;i++){
        while(j<100001&&erk[j]-tav[i]<n/2)j++;
        if(erk[j]-tav[i]>=n/2&&j-i<mx){
            mx=j-i;
            indi=i;
        }
    }
    cout<<mx+1<<endl;//<<indi<<' '<<indi+mx<<endl;
}