// #define _GLIBCXX_DEBUG
#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
using namespace std; using ll = long long; using pii = pair<int, int>; using vi = vector<int>; using vvi = vector<vi>;
#define rep0(TMS) for (int CNT = 0; CNT < (int)(TMS); CNT++)
#define rep(CNT, GOAL) for (int CNT = 0; CNT < (int)(GOAL); CNT++)
#define rep2(CNT, START, GOAL) for (int CNT = (int)(START); CNT < (int)(GOAL); CNT++)
#define rep3(CNT, START, GOAL) for (int CNT = (int)(START); CNT > (int)(GOAL); CNT--)
#define all(CONT) begin(CONT), end(CONT)
#define itrep(ITR, CONT) for (auto ITR = begin(CONT); ITR != end(CONT); ITR++)
#define itrep1(ITR, CONT) for (auto ITR = next(begin(CONT)); ITR != end(CONT); ITR++)
template <typename T> bool chmax(T &a, const T &b) { if (a < b) { a = b; return true; } return false; }
template <typename T> bool chmin(T &a, const T &b) { if (a > b) { a = b; return true; } return false; }
void prec(const int &DIG) { cerr << fixed << setprecision(DIG); cout << fixed << setprecision(DIG); }
template <typename T> void CERR(const T &ELEM) { cerr << ELEM; }
template <typename T, typename ...Ts> void CERR(const T &FIRST, const Ts &...REST) { CERR(FIRST); cerr << ", "; CERR(REST...); }
template <typename T1, typename T2> void CERR(const pair<T1, T2> &PAIR) { cerr << "("; CERR(PAIR.first); cerr << ", "; CERR(PAIR.second); cerr << ")"; }
template <typename T> void CERR(const vector<T> &VEC) { cerr << "{ "; itrep(ITR, VEC) { CERR(*ITR); cerr << ", "; } cerr << "}"; }
template <typename T> void CERR1(const vector<T> &VEC) { cerr << "{ "; itrep1(ITR, VEC) { CERR(*ITR); cerr << ", "; } cerr << "}"; }
template <typename T> void CERR(const set<T> &SET) { cerr << "{ "; itrep(ITR, SET) { CERR(*ITR); cerr << ", "; } cerr << "}"; }
template <typename T> void CERR(const multiset<T> &MULTISET) { cerr << "{ "; itrep(ITR, MULTISET) { CERR(*ITR); cerr << ", "; } cerr << "}"; }
template <typename T1, typename T2> void CERR(const map<T1, T2> &MAP) { cerr << "{ "; itrep(ITR, MAP) { CERR(*ITR); cerr << ", "; } cerr << "}"; }
#define db(OBJ) cerr << #OBJ << ": "; CERR(OBJ); cerr << ", "
#define dbl(OBJ) cerr << #OBJ << ": "; CERR(OBJ); cerr << "\n"
#define db1(OBJ) cerr << #OBJ << ": "; CERR1(OBJ); cerr << "\n"
#define dbs(...) cerr << "(" << #__VA_ARGS__ << "): ("; CERR(__VA_ARGS__); cerr << ")\n"
#define dbvv(VV) cerr << #VV << ": {\n"; rep(CNT, VV.size()) { cerr << #VV << "[" << CNT << "]: "; CERR(VV[CNT]); cerr << ",\n"; } cerr << "}\n"
#define db01(VV) cerr << #VV << ": {\n"; rep(CNT, VV.size()) { cerr << #VV << "[" << CNT << "]: "; CERR1(VV[CNT]); cerr << ",\n"; } cerr << "}\n"
#define db10(VV) cerr << #VV << ": {\n"; rep2(CNT, 1, VV.size()) { cerr << #VV << "[" << CNT << "]: "; CERR(VV[CNT]); cerr << ",\n"; } cerr << "}\n"
#define db11(VV) cerr << #VV << ": {\n"; rep2(CNT, 1, VV.size()) { cerr << #VV << "[" << CNT << "]: "; CERR1(VV[CNT]); cerr << ",\n"; } cerr << "}\n"
#define YN(FLG) cout << (FLG ? "YES" : "NO") << "\n"
#define Yn(FLG) cout << (FLG ? "Yes" : "No") << "\n"
#define yn(FLG) cout << (FLG ? "yes" : "no") << "\n"
// const ll INF = 1'000'000'000'000'000'007;
const int INF = 1'000'000'007;
const ll MOD = 1'000'000'007; // 998'244'353;

int main() {
	ll N, M, K; cin >> N >> M >> K;
	// dbs(N, M, K);
	vector<ll> A(N); rep(i, N) cin >> A[i];
	vector<ll> B(M); rep(i, M) cin >> B[i];
	// dbl(A); dbl(B);
	// Aの[0,i)の累積和，Bの[0,i)の累積和
	vector<ll> accA(N + 1), accB(M + 1);
	rep(i, N) accA[i + 1] = accA[i] + A[i];
	rep(i, M) accB[i + 1] = accB[i] + B[i];
	// dbl(A); dbl(accA); dbl(B); dbl(accB);
	// 机Aの[0,i)(i冊)を読んだとき，Bを何冊[0,j)(j冊)読めるかを考える
	int ans = 0;
	rep(i, N + 1) {
		if (K - accA[i] < 0) break;
		int j = upper_bound(all(accB), K - accA[i]) - begin(accB) - 1;
		// dbl(i); dbs(accA[i], K - accA[i]); dbl(j); dbl(i + j);
		chmax(ans, i + j);
	}

	cout << ans << endl;
}

Measured memory_bytes: 9596