CF #330 C

#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <vector>
#define LL long long
using namespace std;

///vector<int>f;

LL f[200050];

int main(){
/// int n;LL t;
    int n; LL t;
    while(scanf("%d",&n)!=EOF){
    /// f.clear();
        for(int i=0;i<n;i++)
            cin>>f[i];///f.push_back(t);
    /*  for(int i=0;i<n;i++)
            cin>>t,f.push_back(t);*/
        sort(f,f+n);
    //  sort(f.begin(),f.end());
    /// bool flag=n%2?true:false;
    /*  while(n>2){
            if(f[n-1]-f[1]<=f[n-2]-f[0]) f.erase(f.begin()+0);
            else f.erase(f.begin()+n-1);
            n--;
            f.erase(f.begin()+n/2);
            n--;
        }*/
    /// cout<<f[1]-f[0]<<endl;
        LL ans=1e9;
        for(int i=0;i+n/2<n;i++){
            ans=min(ans,f[i+n/2]-f[i]);
        }
        cout<<ans<<endl;
    }
    return 0;
}