#include <cstring>
#include <cassert>
#include <utility>
#include <iostream>
#include <cstdio>
#include <iomanip>
#include <bitset>
#include <chrono>
#include <cstdlib>
#include <functional>
#include <tuple>
#include <climits>
#include <limits>
#include <deque>
#include <list>
#include <array>
#include <stack>
#include <queue>
#include <random>
#include <complex>
#include <string>
#include <vector>
#include <set>
#include <map>
#include <unordered_map>
#include <unordered_set>
#include <algorithm>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

#define ll              long long
#define pi              pair<int,int>
#define pll             pair<ll,ll>
#define pb              push_back
#define F               first
#define S               second
#define vi              vector<int>
#define vll             vector<ll>
#define endl            '\n'
#define all(v)          (v).begin(),(v).end()
#define MP(a,b)         make_pair(a,b)
#define debug(x)        cerr<< #x << " : " << x << endl;
#define debugp(p)       cerr<< #p << " : " << "(" << (p).first << "," << (p).second << ")\n";
#define debugv(v)       cerr<< #v << " : " << "["; for(int i = 0; i < (v).size(); i++) cerr << v[i] << " "; cerr<<"]\n";
#define debugs(m)       cerr<< #m << " : [ "; for(auto itr = m.begin(); itr != m.end(); itr++) cerr <<*itr << " "; cerr << "]\n";
#define debugm(m)       cerr<< #m << " : [ "; for(auto itr = m.begin(); itr != m.end(); itr++) cerr <<"(" << itr->first << "," << itr->second << ") "; cerr << "]\n";

/* ordered set: 
tree<T, null_type,less<T>, rb_tree_tag,tree_order_statistics_node_update>
member functions :
1. order_of_key(k) : number of elements strictly lesser than k
2. find_by_order(k) : k-th element in the set
*/

inline ll modexp(ll x, ll ex , ll md) {
    ll ans = 1ll;
    while (ex > 0) {
        if (ex & 1ll) ans = (ans * x) % md;
        ex >>= 1ll;
        x = (x * x) % md;
    }
    return ans;
}

const int inf = 1e9 + 7;

void Solve(){
    int n , m;
    ll k;
    cin >> n >> m >> k;
    vector<ll> a , b;
    for (int i = 0; i < n; i++){
        ll x;
        cin >> x;
        a.push_back(x);
    }
    for (int i = 0; i < m; i++){
        ll x;
        cin >> x;
        b.push_back(x);
    }
    reverse (all(a));
    reverse(all(b));
    ll t = 0;
    ll bk = 0;
    vector<ll> suffixa (n);
    suffixa[n - 1] = a[n - 1];
    for (int i = n - 2; i >= 0; i--){
        suffixa[i] = suffixa[i + 1] + a[i];
    }
    vector<ll> suffixb(m);
    suffixb[m - 1] = b[m - 1];
    for (int i = m - 2; i >= 0; i--){
        suffixb[i] = suffixb[i + 1] + b[i];
    }
    int ans = 0;
    for (int i = n; i >= 0; i--){
        ll su = 0;
        if (i <= n - 1) su = suffixa[i];
        if (su > k) break;
        ll req = k - su;
        int lo = 0, hi = m - 1;
        int f = m;
        while (lo <= hi){
            int mid = (lo + hi) / 2;
            if (suffixb[mid] <= req){
                f = mid;
                hi = mid - 1;
            } else{
                lo = mid + 1;
            }
        }
        // cout << "for i :" << i << " found f = " << f << endl;
        ans = max (ans , n - i + m - f);
    }
    cout << ans << endl;
}
int main(){
    ios :: sync_with_stdio(false); 
    cin.tie(nullptr); 
    cout.tie(nullptr);
    
    int T = 1;
    // cin >> T;
    for(int tc = 1; tc <= T; tc++){
        // cout << "Case #" << tc << ": ";
        Solve();
    }
    #ifdef LOCAL
    cerr << "Time elapsed\t: " << 1000 * ((double)clock()) / (double)CLOCKS_PER_SEC << "ms\n";       
    #endif
}



Measured memory_bytes: 9520