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

public class yukicoder
{
    public static void Main()
    {
        long[] a = Console.ReadLine().Split(' ').Select(x => long.Parse(x)).ToArray();
        long[] b = Console.ReadLine().Split(' ').Select(x => long.Parse(x)).ToArray();
        long[] c = Console.ReadLine().Split(' ').Select(x => long.Parse(x)).ToArray();
        
        //初回白持ってく数
        long move1 = c[0] - a[1];
        if(move1 <= 0) move1 = 0;
        a[0] -= move1;
        b[0] += move1;
        

        long move2 = 0;

        if(c[1] > b[0])
        {
            Console.WriteLine(a[0] + b[0]);
        }
        else
        {
            Console.WriteLine(a[0] + c[1]);
        }
    }
}