using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.Linq;
using System.Numerics;

namespace AtCoderWorkspace
{
    public class Solver
    {
        public void Solve()
        {
            var cin = new Scanner();
            var n = cin.nextInt();
            var m = cin.nextInt();
            var k = cin.nextLong();
            var a = cin.ArrayLong(n);
            var b = cin.ArrayLong(m);

            var ac = AccSum(a);
            var bc = AccSum(b);
            var tmp = bc.ToList();
            tmp.Add((long)1e9 + 10);
            bc = tmp.ToArray();

            var ans = 0;
            for (int i = 0; i <= n; i++)
            {
                var at = ac[i];
                var rem = k - at;
                if (rem < 0) continue;

                var ok = 0;
                var ng = bc.Length;
                while (Math.Abs(ok - ng) > 1)
                {
                    var mid = (ok + ng) / 2;

                    bool isOK(long index, long key)
                    {
                        return bc[index] <= key;
                    };

                    if (isOK(mid, rem))ok = mid;
                    else ng = mid;
                }
                var score = i + ok;
                ans = Math.Max(ans, score);
            }

            Console.WriteLine(ans);

        }

        long[] AccSum(long[] array)
        {
            var ret = new long[array.Length + 1];
            ret[0] = 0L;
            for (int i = 1; i <= array.Length; i++)
            {
                ret[i] = ret[i - 1] + array[i-1];
            }
            return ret;
        }
    }

    class Scanner
    {
        string[] s;
        int i;

        char[] cs = new char[] { ' ' };

        public Scanner()
        {
            s = new string[0];
            i = 0;
        }

        public string next()
        {
            if (i < s.Length) return s[i++];
            string st = Console.ReadLine();
            while (st == "") st = Console.ReadLine();
            s = st.Split(cs, StringSplitOptions.RemoveEmptyEntries);
            if (s.Length == 0) return next();
            i = 0;
            return s[i++];
        }

        public int nextInt()
        {
            return int.Parse(next());
        }
        public int[] ArrayInt(int N, int add = 0)
        {
            int[] Array = new int[N];
            for (int i = 0; i < N; i++)
            {
                Array[i] = nextInt() + add;
            }
            return Array;
        }

        public int[] DPArrayInt(int N, int ex)
        {
            int[] Array = new int[N + ex];
            for (int i = 0; i < N; i++)
            {
                Array[i] = nextInt();
            }
            return Array;
        }

        public long nextLong()
        {
            return long.Parse(next());
        }

        public long[] ArrayLong(int N, long add = 0)
        {
            long[] Array = new long[N];
            for (int i = 0; i < N; i++)
            {
                Array[i] = nextLong() + add;
            }
            return Array;
        }

        public long[] DPArrayLong(int N, int ex)
        {
            long[] Array = new long[N + ex];
            for (int i = 0; i < N; i++)
            {
                Array[i] = nextLong();
            }
            return Array;
        }

        public double nextDouble()
        {
            return double.Parse(next());
        }


        public double[] ArrayDouble(int N, double add = 0)
        {
            double[] Array = new double[N];
            for (int i = 0; i < N; i++)
            {
                Array[i] = nextDouble() + add;
            }
            return Array;
        }
    }

    class Program
    {
        static void Main(string[] s) => new Solver().Solve();
    }
}


Measured memory_bytes: 77480