import java.awt.geom.Line2D;
import java.awt.geom.Point2D;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.net.ConnectException;
import java.rmi.dgc.Lease;
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Calendar;
import java.util.Collections;
import java.util.Deque;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.NoSuchElementException;
import java.util.Objects;
import java.util.Set;
import java.util.Stack;
import java.util.TreeMap;
import java.util.TreeSet;

import static java.util.Comparator.*;

public class Main {
	public static void main(String[] args) {
		Main main = new Main();
		main.solve();
		main.out.close();
	}
	// ======================================================================
	int N, M, K;
//	int[] A = new int[2*100010];
//	int[] B = new int[2*100010];
	long[] RA;
	long[] RB;
	public void solve() {
		N = ni();
		M = ni();
		K = ni();
		RA = new long[N+1];
		RB = new long[M+1];
		int a, b;
		for (int i = 0; i < N; i++) {
			a = ni();
			RA[i+1] = RA[i] + a;
		}
		for (int i = 0; i < M; i++) {
			b = ni();
			RB[i+1] = RB[i] + b;
		}
		int ans = 0, index;
		long wk;
		for (int i = 0; i <= N; i++) {
			wk = (long)K - RA[i];
			if(wk < 0)		break;
			// 配列 a の中で key 以下（f=true)または、より小さい（f=false)、一番大きい値を返す（なければ -1 を返す）
			index = binarySearchLeftMax(RB, true, wk);
			if(index == -1)	break;
			ans = Math.max(ans, i + index);
		}
		out.println(ans);
	}
	// 配列のバイナリーサーチ　２
	boolean isLeftMax(long[] a, boolean f, int index, long key) {
		if (f && a[index] <= key)		return true;		// 以下
		else if (!f && a[index] < key)	return true;		// より小さい
		else 							return false;	
	}
	// 配列 a の中で key 以下（f=true)または、より小さい（f=false)、一番大きい値を返す（なければ -1 を返す）
	int binarySearchLeftMax(long[] a, boolean f, long key) {	
		int ng = -1; 
		int ok = (int)a.length;
		
		while (Math.abs(ok - ng) > 1) {	
			int mid = (ok + ng) / 2;	
			
			if (isLeftMax(a, f, mid, key))	ng = mid;	// 上半分を対象とする
			else 							ok = mid;	// 下半分を対象とする
		}	
		return ng;		// ←　ここで返すのは　isOK() が true の時にセットする方（ok / ng)
	}

		
	// ------------------------------------------
	// ライブラリ
	// ------------------------------------------
	// Print
	private PrintWriter out = new PrintWriter(System.out);
	
	// Scanner
	private FastScanner scan = new FastScanner();
	int ni(){ return scan.nextInt();}
	int[] ni(int n){int[] a = new int[n]; for(int i = 0; i < n; i++){a[i] = ni();} return a;}
	int[][] ni(int y, int x){int[][] a = new int[y][x];
	for(int i = 0; i < y; i++){for(int j = 0; j < x; j++){a[i][j] = ni();}} return a;}
	long nl(){return scan.nextLong();}
	long[] nl(int n){long[] a = new long[n]; for(int i = 0; i < n; i++){a[i] = nl();} return a;}
	long[][] nl(int y, int x){long[][] a = new long[y][x];
	for(int i = 0; i < y; i++){for(int j = 0; j < x; j++){a[i][j] = nl();}} return a;}
	String ns(){return scan.next();}
	String[] ns(int n){String[] a = new String[n]; for(int i = 0; i < n; i++){a[i] = ns();} return a;}
	String[][] ns(int y, int x){String[][] a = new String[y][x];
	for(int i = 0; i < y; i++){for(int j = 0; j < x; j++){a[i][j] = ns();}} return a;}
}
class FastScanner {
	private final InputStream in = System.in;
	private final byte[] buffer = new byte[1024];
	private int ptr = 0;
	private int buflen = 0;
	private boolean hasNextByte() {
		if (ptr < buflen) {
			return true;
		}else{
			ptr = 0;
			try {
				buflen = in.read(buffer);
			} catch (IOException e) {
				e.printStackTrace();
			}
			if (buflen <= 0) {
				return false;
			}
		}
		return true;
	}
	private int readByte() { if (hasNextByte()) return buffer[ptr++]; else return -1;}
	private static boolean isPrintableChar(int c) { return 33 <= c && c <= 126;}
	public boolean hasNext() { while(hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; return hasNextByte();}
	public String next() {
		if (!hasNext()) throw new NoSuchElementException();
		StringBuilder sb = new StringBuilder();
		int b = readByte();
		while(isPrintableChar(b)) {
			sb.appendCodePoint(b);
			b = readByte();
		}
		return sb.toString();
	}
	public long nextLong() {
		if (!hasNext()) throw new NoSuchElementException();
		long n = 0;
		boolean minus = false;
		int b = readByte();
		if (b == '-') {
			minus = true;
			b = readByte();
		}
		if (b < '0' || '9' < b) {
			throw new NumberFormatException();
		}
		while(true){
			if ('0' <= b && b <= '9') {
				n *= 10;
				n += b - '0';
			}else if(b == -1 || !isPrintableChar(b)){
				return minus ? -n : n;
			}else{
				throw new NumberFormatException();
			}
			b = readByte();
		}
	}
	public int nextInt() {
		long nl = nextLong();
		if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) throw new NumberFormatException();
		return (int) nl;
	}
	public double nextDouble() { return Double.parseDouble(next());}
}


Measured memory_bytes: 47320