#line 2 "../../library/template.hpp"
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pl = pair<ll, ll>;
using vl = vector<ll>;
#define rep(i, n) for(ll i = 0; i < (ll)n; i++)
#define rep3(i, l, r) for(ll i = l; i < (ll)r; i++)
#define per(i, n) for(ll i = (ll)n-1; i >= 0; i--)
#define per3(i, l, r) for(ll i = (ll)r-1; i >= (ll)l; i--)
#define all(v) begin(v), end(v)
template<class T, class U> inline void cmax(T &a, U b) { if (a < b) a = b; }
template<class T, class U> inline void cmin(T &a, U b) { if (a > b) a = b; }
constexpr char el = '\n';
template<class T, class U> ostream &operator<<(ostream &os, const pair<T, U> &p) { os << p.first << " " << p.second; return os; }
template<class T, class U> istream &operator>>(istream &is, pair<T, U> &p) { is >> p.first >> p.second; return is; }
template<class T> ostream &operator<<(ostream &os, const vector<T> &v) { rep(i, v.size()) os << v[i] << (i+1 != v.size() ? " " : ""); return os; }
template<class T> istream &operator>>(istream &is, vector<T> &v) { for(T &i : v) is >> i; return is; }
struct IoSetup {
  IoSetup() { cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(15); cerr << fixed << setprecision(15); }
} io_setup;
#line 3 "../../library/cumulative_sum.hpp"

template<class T>
struct CumulativeSum {
  vector<T> v;

  CumulativeSum(size_t n) : v(n+1) {};
  CumulativeSum(vector<T> v_) {
    v.resize(v_.size()+1);
    rep(i, v_.size())
      v[i+1] = v_[i];
  };

  void add(size_t i, T x) {
    v[i+1] += x;
  }

  // O(N)
  void build() {
    if (v.size() == 0) return;
    rep(i, v.size()-1)
      v[i+1] += v[i];
  }

  // O(1) sum [l, r]
  T sum(size_t l, size_t r) const {
    return l == 0 ? v[r+1] : v[r+1]-v[l];
  }

  // O(1) sum [0, r]
  T sum(size_t r) const {
    return v[r+1];
  }

  T& operator[](size_t i) {
    return v[i];
  }

  const T& operator[](size_t i) const {
    return v[i];
  }
};
#line 3 "../../library/debug.hpp"

// https://codeforces.com/blog/entry/68809
void debug_print(int x) {cerr << x;}
void debug_print(long x) {cerr << x;}
void debug_print(long long x) {cerr << x;}
void debug_print(unsigned x) {cerr << x;}
void debug_print(unsigned long x) {cerr << x;}
void debug_print(unsigned long long x) {cerr << x;}
void debug_print(float x) {cerr << x;}
void debug_print(double x) {cerr << x;}
void debug_print(long double x) {cerr << x;}
void debug_print(char x) {cerr << '\'' << x << '\'';}
void debug_print(const char *x) {cerr << '\"' << x << '\"';}
void debug_print(const string &x) {cerr << '\"' << x << '\"';}
void debug_print(bool x) {cerr << (x ? "true" : "false");}
template<typename T, typename V> void debug_print(const pair<T, V> &x) {cerr << '{'; debug_print(x.first); cerr << ','; debug_print(x.second); cerr << '}';}
template<typename T> void debug_print(const T &x) {int f = 0; cerr << '{'; for (auto &i: x) cerr << (f++ ? "," : ""), debug_print(i); cerr << "}";}

void debug_print_() {cerr << "]\n";}
template <typename T, typename... V>
void debug_print_(T t, V... v) {debug_print(t); if (sizeof...(v)) cerr << ", "; debug_print_(v...);}

#ifdef LOCAL
  #define debug(x...) cerr << "[" << #x << "] = ["; debug_print_(x)
#else
  #define debug(x...)
#endif
#line 4 "c.cpp"

int main() {
  ll n, m, k;
  cin >> n >> m >> k;

  vl a(n+1), b(m+1);
  rep(i, n) {
    cin >> a[i+1];
  }
  rep(i, m) {
    cin >> b[i+1];
  }

  rep(i, n) {
    a[i+1] += a[i];
  }
  rep(i, m) {
    b[i+1] += b[i];
  }
  ll ans = 0;

  debug(a);
  debug(b);

  rep(i, n+1) {
    if (a[i] > k) break;
    ll cnt = i+(lower_bound(all(b), k-a[i]+1)-b.begin()-1);
    cerr << cnt << el;
    cmax(ans, cnt);
  }
  cout << ans << el;
}


Measured memory_bytes: 6368