Go: package main

import (
	"bufio"
	"fmt"
	"math"
	"os"
	"strconv"
)

func configure(scanner *bufio.Scanner) {
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 1000005), 1000005)
}
func getNextString(scanner *bufio.Scanner) string {
	scanned := scanner.Scan()
	if !scanned {
		panic("scan failed")
	}
	return scanner.Text()
}
func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}
func getNextInt64(scanner *bufio.Scanner) int64 {
	i, _ := strconv.ParseInt(getNextString(scanner), 10, 64)
	return i
}
func getNextFloat64(scanner *bufio.Scanner) float64 {
	i, _ := strconv.ParseFloat(getNextString(scanner), 64)
	return i
}
func main() {
	fp := os.Stdin
	wfp := os.Stdout
	extra := 0
	if os.Getenv("I") == "IronMan" {
		fp, _ = os.Open(os.Getenv("END_GAME"))
		extra = 100
	}
	scanner := bufio.NewScanner(fp)
	configure(scanner)
	writer := bufio.NewWriter(wfp)
	defer func() {
		r := recover()
		if r != nil {
			fmt.Fprintln(writer, r)
		}
		writer.Flush()
	}()
	solve(scanner, writer)
	for i := 0; i < extra; i++ {
		fmt.Fprintln(writer, "-----------------------------------")
		solve(scanner, writer)
	}
}
func solve(scanner *bufio.Scanner, writer *bufio.Writer) {
	for {
		n := getNextInt(scanner)
		if n == 0 {
			break
		}
		sum := 0
		ll := make([]int, 1)
		rr := make([]int, 1)
		for i := 0; i < n/2; i++ {
			a := getNextInt(scanner)
			sum += a
			ll = merge(ll, a)
		}
		for i := n / 2; i < n; i++ {
			a := getNextInt(scanner)
			sum += a
			rr = merge(rr, a)
		}
		r := len(rr) - 1
		var ans cint
		ans = math.MaxInt32
		for l := 0; l < len(ll); l++ {
			for r >= 0 && ll[l]+rr[r] > 0 {
				r--
			}
			if r >= 0 {
				ans.minAs(cint(ll[l] + rr[r]).abs())
			}
			if r+1 < len(rr) {
				ans.minAs(cint(ll[l] + rr[r+1]).abs())
			}
		}
		fmt.Fprintln(writer, ans)
	}
}

type cint int64

func (ct *cint) minAs(x cint) *cint {
	*ct = ct.min(x)
	return ct
}
func (ct *cint) maxAs(x cint) *cint {
	*ct = ct.max(x)
	return ct
}
func (ct cint) min(x cint) cint {
	if ct > x {
		return x
	}
	return ct
}
func (ct cint) max(x cint) cint {
	if ct < x {
		return x
	}
	return ct
}
func (ct cint) abs() cint {
	return ct.max(-ct)
}
func merge(aa []int, a int) []int {
	n := len(aa)
	bb := make([]int, n)
	cc := make([]int, 0)
	for i := 0; i < n; i++ {
		bb[i] = aa[i] + a
		aa[i] = aa[i] - a
	}
	i := 0
	j := 0
	for i < n || j < n {
		if first(aa, bb, i, j, n) {
			cc = append(cc, aa[i])
			i++
			continue
		}
		cc = append(cc, bb[j])
		j++
	}
	return cc
}
func first(aa, bb []int, a, b, n int) bool {
	if a == n {
		return false
	}
	if b == n {
		return true
	}
	return aa[a] < bb[b]
}

C++: // includes
#include <bits/stdc++.h>

// macros
#define ll long long int
#define pb emplace_back
#define mk make_pair
#define pq priority_queue
#define FOR(i, a, b) for(int i=(a);i<(b);++i)
#define rep(i, n) FOR(i, 0, n)
#define rrep(i, n) for(int i=((int)(n)-1);i>=0;i--)
#define irep(itr, st) for(auto itr = (st).begin(); itr != (st).end(); ++itr)
#define irrep(itr, st) for(auto itr = (st).rbegin(); itr != (st).rend(); ++itr)
#define vrep(v, i) for(int i = 0; i < (v).size(); i++)
#define all(x) (x).begin(),(x).end()
#define sz(x) ((int)(x).size())
#define UNIQUE(v) v.erase(unique(v.begin(), v.end()), v.end())
#define FI first
#define SE second
#define dump(a, n) for(int i = 0; i < n; i++)cout << a[i] << "\n "[i + 1 != n];
#define dump2(a, n, m) for(int i = 0; i < n; i++)for(int j = 0; j < m; j++)cout << a[i][j] << "\n "[j + 1 != m];
#define bit(n) (1LL<<(n))
#define INT(n) int n; cin >> n;
#define LL(n) ll n; cin >> n;
#define DOUBLE(n) double n; cin >> n;
using namespace std;

//  types
typedef pair<int, int> P;
typedef pair<ll, int> Pl;
typedef pair<ll, ll> Pll;
typedef pair<double, double> Pd;
typedef complex<double> cd;
 
// constants
const int inf = 1e9;
const ll linf = 1LL << 50;
const double EPS = 1e-10;
const int mod = 1e9 + 7;
const int dx[4] = {-1, 0, 1, 0};
const int dy[4] = {0, -1, 0, 1};

// solve
template <class T>bool chmax(T &a, const T &b){if(a < b){a = b; return 1;} return 0;}
template <class T>bool chmin(T &a, const T &b){if(a > b){a = b; return 1;} return 0;}
template <typename T> istream &operator>>(istream &is, vector<T> &vec){for(auto &v: vec)is >> v; return is;}
template <typename T> ostream &operator<<(ostream &os, const vector<T>& vec){for(int i = 0; i < vec.size(); i++){ os << vec[i]; if(i + 1 != vec.size())os << " ";} return os;}
template <typename T> ostream &operator<<(ostream &os, const set<T>& st){for(auto itr = st.begin(); itr != st.end(); ++itr){ os << *itr; auto titr = itr; if(++titr != st.end())os << " ";} return os;}
template <typename T> ostream &operator<<(ostream &os, const unordered_set<T>& st){for(auto itr = st.begin(); itr != st.end(); ++itr){ os << *itr; auto titr = itr; if(++titr != st.end())os << " ";} return os;}
template <typename T> ostream &operator<<(ostream &os, const multiset<T>& st){for(auto itr = st.begin(); itr != st.end(); ++itr){ os << *itr; auto titr = itr; if(++titr != st.end())os << " ";} return os;}
template <typename T> ostream &operator<<(ostream &os, const unordered_multiset<T>& st){for(auto itr = st.begin(); itr != st.end(); ++itr){ os << *itr; auto titr = itr; if(++titr != st.end())os << " ";} return os;}
template <typename T1, typename T2> ostream &operator<<(ostream &os, const pair<T1, T2> &p){os << p.first << " " << p.second; return os;}
template <typename T1, typename T2> ostream &operator<<(ostream &os, const map<T1, T2> &mp){for(auto itr = mp.begin(); itr != mp.end(); ++itr){ os << itr->first << ":" << itr->second; auto titr = itr; if(++titr != mp.end())os << " "; } return os;}
template <typename T1, typename T2> ostream &operator<<(ostream &os, const unordered_map<T1, T2> &mp){for(auto itr = mp.begin(); itr != mp.end(); ++itr){ os << itr->first << ":" << itr->second; auto titr = itr; if(++titr != mp.end())os << " "; } return os;}


int main(int argc, char const* argv[])
{
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout << fixed << setprecision(20);
  while(true){
  	INT(n); if(n == 0)break;
  	vector<ll> a(n); cin >> a;
  	constexpr int m = 20000000;
  	bitset<m> bt(0);
  	bt.set(0);
  	rep(i, n){
  		bt |= (bt << a[i]);
  	}
  	ll sum = 0; rep(i, n)sum += a[i];
  	ll res = linf;
  	rep(i, m){
  		if(i > sum)break;
  		if(bt[i]){
  			res = min(res, abs(i - sum + (ll)i));
  		}
  	}
  	cout << res << endl;
  }
  return 0;
}

C++: #include<iostream>
#include<vector>
#include<algorithm>
#include<cmath>

using namespace std;

int main()
{
	int n;
	
	for(;;)
	{
		vector<int> num;
		cin >> n;
		if(n==0)
			break;
		for(int i=0;i<n;i++)
		{
			int a;
			cin >> a;
			num.push_back(a);
		}
		
		sort(num.begin(),num.end());
		
		int a=0,b=0;
		int a_f=1;
		
		if(num.size()==2)
		{
			cout << num[1]-num[0] << endl;
		}
		else
		{
			if(num.size()%2==0)
			{
				for(int i=0,j=num.size()-1;i<j;i++,j--)
				{
					if(a_f==1)
					{
						a+=num[i]+num[j];
						a_f=0;
					}
					else
					{
						b+=num[i]+num[j];
						a_f=1;
					}
				}
			}
			else
			{
				for(int i=1,j=num.size()-1;i<=j || i<num.size();i++,j--)
				{
					if(a_f==1)
					{
						a+=num[i]+num[j];
						a_f=0;
					}
					else
					{
						b+=num[i]+num[j];
						a_f=1;
					}
				}
				if(a<=b)
					a+=num[0];
				else
					b+=num[0];
			}
			
			int ans_a,ans_b;
			ans_a=max(a,b);
			ans_b=min(a,b);
//			cout << "ans_a:" << ans_a << " ans_b:" << ans_b << endl;
			cout << ans_a-ans_b << endl;
		}
	}
}

C++: #include <iostream>
#include <vector>
#include <algorithm>
#include <functional>
#include <cstdlib>
using namespace std;

int main() {
  int n;
  while(cin >>n, n) {
    vector<int> v;
    int x;
    for(int i=0; i<n; i++) {
      cin >> x;
      v.push_back(x);
    }
    sort(v.begin(),v.end(), greater<int>());

    int a=0, b=0;
    for(int i=0; i<v.size(); i++) {
      if (a>b)
        b += v[i];
      else
        a += v[i];
    }
    cout << abs(b-a) << endl;
  }
}