///   BISMILLAHIR RAHMANIR RAHEEM
///   ALLAH IS WATCHING ME
///   ALLAH save us from COVID-19.Amin.

///   █▀█─█──█──█▀█─█─█
///   █▄█─█──█──█▄█─█▄█
///   █─█─█▄─█▄─█─█─█─█

///   كُلُّ نَفْسٍ ذَآئِقَةُ الْمَوْت
///   Every soul shall taste death.

/// TODO::

#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/detail/standard_policies.hpp>

///  order_of_key return number of elements less than x.
///  find_by_order return index.

using namespace std;
using namespace __gnu_pbds;


#define MOHAMMAD  ios::sync_with_stdio(0);cin.tie(0);
#define all(x)    (x).begin(), (x).end()
#define AE        cout << fixed << setprecision(10);

int dx8[] = {0, 0, 1, 1, 1, -1, -1, -1}; // 8-direction.......
int dy8[] = {1,-1, 1, -1, 0, 0, -1, 1};
int dx4[]= {1,-1,0,0}; // 4-direction...........
int dy4[]= {0,0,1,-1};

typedef tree< int, null_type, less<int>, rb_tree_tag,tree_order_statistics_node_update> ordered_set;
typedef tree<pair<int, int>,null_type,less<pair<int, int>>,rb_tree_tag,tree_order_statistics_node_update> ordered_multiset;

//debug
template<typename F,typename S>ostream&operator<<(ostream&os,const pair<F,S>&p){return os<<"("<<p.first<<", "<<p.second<<")";}
template<typename T>ostream&operator<<(ostream&os,const vector<T>&v){os<<"{";for(auto it=v.begin();it!=v.end();++it){if(it!=v.begin())os<<", ";os<<*it;}return os<<"}";}
template<typename T>ostream&operator<<(ostream&os,const set<T>&v){os<<"[";for(auto it=v.begin();it!=v.end();++it){if(it!=v.begin())os<<",";os<<*it;}return os<<"]";}
template<typename T>ostream&operator<<(ostream&os,const multiset<T>&v) {os<<"[";for(auto it=v.begin();it!=v.end();++it){if(it!=v.begin())os<<", ";os<<*it;}return os<<"]";}
template<typename F,typename S>ostream&operator<<(ostream&os,const map<F,S>&v){os<<"[";for(auto it=v.begin();it!=v.end();++it){if(it!=v.begin())os<<", ";os<<it->first<<" = "<<it->second;}return os<<"]";}
#define dbg(args...) do {cerr << #args << " : "; faltu(args); } while(0)
void faltu(){cerr << endl;}
template<typename T>void faltu(T a[],int n){for(int i=0;i<n;++i)cerr<<a[i]<<' ';cerr<<endl;}
template<typename T,typename...hello>void faltu(T arg,const hello&...rest){cerr<<arg<<' ';faltu(rest...);}
//#else
//#define dbg(args...)
//***********************************************  The END **********************************************************************************************************************************
using ll = long long;
ll n , m , k;

const ll N = 2e5 + 1;
ll a[N+1] , b[N+1];

int main()
{

  /// MOHAMMAD


 cin >> n >> m >> k;

 for ( ll i = 1 ;i<=n ; ++i ) cin >> a[i];
 for ( ll i = 1 ; i<=m ; ++i ) cin >> b[i];


 vector < ll > pa ( n+1 , 0 ) , pb ( m + 1 , 0 );


 //ll pa[n+1] = { 0 } , pb[m+1] = { 0 };

 for ( ll i = 1 ; i<=n ; ++i ){
      pa[i] = pa[i-1] + a[i];
 }

 for ( ll i = 1 ; i<=m ; ++i ){
      pb[i] = pb[i-1] + b[i];
 }
 ll mx = 0;
 for ( ll i = 0 ; i<=m ; ++i ){

      ll other = k - pb[i];

      if( other<0) continue;

      ll idx = lower_bound( pa.begin() , pa.end() , other ) - pa.begin();

      if ( idx>n or pa[idx]>other ) idx--;

      mx = max ( mx , i + idx );
 }




 cout << mx << "\n";

}

/*





  Alhamdulillah
*/



Measured memory_bytes: 9540