#include <bits/stdc++.h>
using namespace std;
#define REP(i,x,n) for(int i=x;i<(int)n;i++)
#define rep(i,n) REP(i,0,n)
#define sp(p) cout<<setprecision(16)<<fixed<<p<<endl;
#define all(a) a.begin(),a.end()
#define rall(a) a.rbegin(),a.rend()
#define SORT(a) sort(all(a))
#define RSORT(a) sort(rall(a))
#define UNIQ(a) unique(all(a))
#define UNIQNUM(a) UNIQ(a)-a.begin()
#define UNIQIT(a) a.erase(UNIQ(a), a.end());
#define VOUT(v,i) rep(i,v.size())cout<<v[i]<<(i==v.size()-1?"\n":" ");
#define vout(v) VOUT(v,z);
#define vdbg(v,i) cout<<#v<<": ";for(int i=0;i<(int)v.size();i++){cout<<v[i]<<" ";}cout<<"\n";
#define vmin(v) *min_element(all(v))
#define vmax(v) *max_element(all(v))
#define vsum(v) accumulate(all(v), 0LL)
#define MOUT(m,r,c) rep(i,r){rep(j,c){cout<<m[i][j]<<" ";}cout<<endl;}
#define mout(m) MOUT(m,m.size(),m[0].size())
#define debg(a) cout<<#a<<": "<<a<<endl;
#define show(a) for(cont &y:a){for(cont &x:y){cout<<x<<" ";}cout<<endl;}
#define digit(a) to_string(a).length();
template<class T>inline int out(const T &t){ print(t); putchar('\n'); return 0; }
// template<class T>inline T gcd(T a,T b){if(b==0)return a; return(gcd(b,a%b));}
// template<class T>inline T lcm(T a,T b){return a/gcd(a,b)*b;}
bool is_palindrome(string s){return s == string(s.rbegin(),s.rend());}
typedef long long ll;
typedef long double ld;
typedef pair<ll,ll> P;
typedef vector<ll> V;
typedef vector<vector<ll>> VV;
// const long long MOD=1000000007;
const long long INF = 1e18;
#define EPS (1e-7)
#define PI (acos(-1))
template<class T>
inline bool chmax(T &a, T b) {
    if(a < b) { a = b; return true; }
    return false;
}
template<class T>
inline bool chmin(T &a, T b) {
    if(a > b) { a = b; return true; }
    return false;
}



int main(){
    long long N;
    scanf("%lld",&N);
    long long M;
    scanf("%lld",&M);
    long long K;
    scanf("%lld",&K);
    std::vector<long long> A(N);
    for(int i = 0 ; i < N ; i++){
        scanf("%lld",&A[i]);
    }
    std::vector<long long> B(M);
    for(int i = 0 ; i < M ; i++){
        scanf("%lld",&B[i]);
    }
    std::vector<long long> aacc(N);
    aacc[0]=A[0];
    for (long long i = 1; i < N; i++) {
        aacc[i]=aacc[i-1]+A[i];
    }
    std::vector<long long> bacc(M);
    bacc[0]=B[0];
    for (long long i = 1; i < M; i++) {
        bacc[i]=bacc[i-1]+B[i];
    }
    // vout(aacc)
    // vout(bacc)

    // ll cnt=0;
    // for (long long i = 0; i < N; i++) {
    //     if(aacc[i]>K) break;
    //     ll ng = 0, ok = M-1;
    //     while (abs(ok - ng) > 1) {
    //       ll mid = (ok + ng) / 2;
    //     // debg(aacc[i]+bacc[mid]);
    //     if (aacc[i]+bacc[mid]>K) {
    //         ok = mid;
    //       } else {
    //         ng = mid;
    //       }
    //     }
    //     // debg(cnt);
    //     // debg(i);
    //     // debg(ok);
    //     // debg(ng);
    //     if(aacc[i]+bacc[ok]>K) ok--;
    //     chmax(cnt, i+1 + ok+1);
    // }

    ll cnt=0;
    for (long long i = 0; i < N; i++) {
        if(aacc[i]>K) break;
        // auto itr = lower_bound(all(bacc), K-aacc[i]);
        auto itr = upper_bound(all(bacc), K-aacc[i]);
        // debg(*itr);
        ll idx=itr-bacc.begin();
        // debg(i);
        // debg(idx);
        while(idx>=0 && aacc[i]+bacc[idx]>K) idx--;
        chmin(idx, M-1);
        chmax(cnt, i+1 + idx+1);
    }

    ll acnt=0;
    for (long long i = 0; i < N; i++) {
        if(aacc[i]<=K) {
            acnt++;
        }
    }
    chmax(cnt, acnt);

    ll bcnt=0;
    for (long long i = 0; i < M; i++) {
        if(bacc[i]<=K) {
            bcnt++;
        }
    }
    // debg(bcnt);
    chmax(cnt, bcnt);

    cout << cnt << endl;

    return 0;
}


Measured memory_bytes: 9580