using System;
using System.Collections.Generic;
using System.Linq;

namespace y
{
    class Program
    {
        static void Main(string[] args)
        {
            var n = int.Parse(Console.ReadLine());
            var s = new int[n];

            int a = 0;
            int[] k1 = new int[n];
            int[] k2 = new int[n];
            for (int i = 0; i < n; i++)
            {
                var u = Console.ReadLine().Split().Select(x => int.Parse(x)).ToArray();
                k1[i] = u[0];
                k2[i] = u[1];
                a += u[0];
            }


            var li1 = new List<int>();
            li1.Add(a);
            for (int i = 0; i < s.Length; i++)
            {
                int e = li1.Count;
                var li2 = new List<int>();
                for (int j = 0; j < e; j++)
                {
                    li2.Add(li1[j]);
                    li2.Add(li1[j] - (k1[i] + k2[i]));
                }
                li1 = li2;
            }

            var ans = li1.Min(x => Math.Abs(x));
            Console.WriteLine(ans);
        }
    }
}