#include <iostream>
#include <string>
#include <cstring>
#include <stack>
#include <queue>
#include <cctype>
#include <algorithm>
#include <vector>
#include <map>
#include <set>
#include <cmath>
#include <stdlib.h>
#include <tuple>
#include <iomanip>
#include <iterator>
#include <stdio.h>
#include <fstream>
#include <time.h>
using namespace std;
const double PI = 3.14159265358979323846;
const long long int MOD = 1000000000 + 7;

struct UnionFind {
    vector<int> parent;

    UnionFind(int N) : parent(N) {
        for (int i = 0; i < N; i++) {
            parent[i] = -1;
        }
    }

    int root(int i) {
        if (parent[i] < 0) {
            return i;
        }
        return (parent[i] = root(parent[i]));
    }

    bool unite(int from, int to) {
        int rx = root(from);
        int ry = root(to);
        if (rx != ry) {
            parent[ry] += parent[rx];
            parent[rx] = ry;

            return true;
        }
        else {
            return false;
        }
    }

    bool same(int x, int y) {
        return root(x) == root(y);
    }

    int treeSize(int x) {


        return -parent[root(x)];
    }
};

long long int modpow(long long int base, long long int pow, long long int mod) {
    if (pow == 1) {
        return base;
    }
    else if (pow == 0) {
        return 1;
    }

    if (pow % 2 == 0) {
        auto temp = modpow(base, pow / 2, mod);
        return (temp * temp) % mod;
    }
    else {
        return (base * modpow(base, pow - 1, mod)) % mod;
    }
}

long long int moddiv(long long int X, long long int Y, long long int mod) {
    auto fermatDiv = modpow(Y, mod - 2, mod);

    return (X * fermatDiv) % mod;
}

long long modCombination(long long left, long long right, long long int mod) {
    long long answer = 1;
    if (left > right) {
        for (long long i = 0; i < right; i++) {
            answer = (answer * (left - i)) % mod;
            answer = moddiv(answer, (i + 1), mod);
        }
    }
    return answer;
}

bool IsPrime(long long N) {
    if (N == 1) {
        return false;
    }
    for (long long i = 2; i * i <= N; i++) {
        if (N % i == 0) {
            return false;
        }
    }


    return true;
}


vector<pair<long long, long long> > prime_factorize(long long N) {
    vector<pair<long long, long long> > res;
    for (long long a = 2; a * a <= N; ++a) {
        if (N % a != 0) continue;
        long long ex = 0; // 指数

        // 割れる限り割り続ける
        while (N % a == 0) {
            ++ex;
            N /= a;
            
        }

        // その結果を push
        res.push_back({ a, ex });
    }

    // 最後に残った数について
    if (N != 1) res.push_back({ N, 1 });
    return res;
}

map<long long, set<long long>> cache;
set<long long> enum_divisors(long long N) {
    set<long long> res;
    for (long long i = 1; i * i <= N; ++i) {
        if (N % i == 0) {
            res.insert(i);

            if (cache.count(N / i) > 0) {
                auto copy = cache[N / i];
                auto copy2 = cache[N / i];
                for (auto v : res) {
                    if (v != 1) {
                        //cout << "v*" << v << endl;
                        for (auto itr = copy2.begin(); itr != copy2.end(); itr++) {
                            copy.insert(*itr * v);
                        }
                        break;
                    }
                }
                cache[N] = copy;
                return copy;
            }

            // 重複しないならば i の相方である N/i も push
            if (N / i != i) res.insert(N / i);

            
        }
    }

    cache[N] = res;
    return res;
}

long long euclid(long long a, long long b) {
    if (a > b) {
        long long temp = b;
        b = a;
        a = temp;
    }
    if (b % a == 0) {
        return a;
    }
    else {
        return euclid(a, b - a);
    }
}

long long gcd(long long a, long long b) {
    if (b > a) {
        long long temp = b;
        b = a;
        a = temp;
    }
    //cout << "a:" << a << "b:" << b << endl;
    long long c = a % b;
    if (c == 0) {
        return b;
    }
    else {
        return gcd(b, c);
    }
}




int main() {
    long long N, M, K;
    cin >> N >> M >> K;

    vector<long long> A(N), B(M);

    for (long long i = 0; i < N; i++) {
        long long temp;
        cin >> temp;
        A[i] = temp;
    }

    for (long long i = 0; i < M; i++) {
        long long temp;
        cin >> temp;
        B[i] = temp;
    }

    vector<long long> Asum(N+1), Bsum(M+1);

    Asum[0] = 0;
    for (long long i = 1; i <= N; i++) {
        Asum[i] = A[i-1] + Asum[i - 1];
    }

    Bsum[0] = 0;
    for (long long i = 1; i <= M; i++) {
        Bsum[i] = B[i-1] + Bsum[i - 1];
    }

    long long max = 0;
    long long Ahead = 0, Bhead = 0;

    for (long long i = 0; i <= M; i++) {
        if (Bsum[i] <= K) {
            Bhead = i;
            max = i;
        }
    }

    bool isFinish = false;
    for (long long i = Bhead; i >= 0; i--) {
        long long currentTime = Bsum[i];
        for (long long j = Ahead; j <= N; j++) {
            if (Asum[j] + currentTime > K) {
                Ahead = j - 1;
                if (Ahead < 0) {
                    Ahead = 0;
                }
                break;
            }

            if (j == N) {
                Ahead = N;
                isFinish = true;
            }
        }

        if (currentTime + Asum[Ahead] <= K && i + Ahead > max) {
            max = i + Ahead;
        }

        if (isFinish) {
            break;
        }
    }

    cout << max << endl;

    /*vector<vector<long long>> dp(N+M+1, vector<long long>(N+1));

    long long Aindex = 0, Bindex = 0;
    bool isAsearch = true, isBsearch = true;
    
    while (isAsearch || isBsearch) {
        if (isAsearch) {
            for (long long i = Aindex + Bindex; i >= Aindex; i--) {
                if (dp[i][Aindex] + A[Aindex] <= K) {
                    dp[i + 1][Aindex + 1] = dp[i][Aindex] + A[Aindex];
                }
            }
            Aindex++;
            if (Aindex == N) {
                isAsearch = false;
            }
        }

        if (isBsearch) {
            for (long long i = Aindex + Bindex; i >= Bindex; i--) {
                if (dp[i][i - Aindex] + B[Bindex] <= K) {
                    dp[i + 1][i-Aindex] = dp[i][i-Aindex] + B[Bindex];
                }
            }
        }
    }*/


    /*long long N;
    cin >> N;

    long long answer = 0;
    for (long long K = 1; K <= N; K++) {
        auto p = enum_divisors(K);
        long long temp = p.size() * K;
        //cout << "size:" << p.size() << endl;
        answer += temp;
    }

    cout << answer << endl;*/
    return 0;
}

Measured memory_bytes: 9608