import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 *
 * @author Spandan Mishra
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        CTsundoku solver = new CTsundoku();
        solver.solve(1, in, out);
        out.close();
    }

    static class CTsundoku {
        public void solve(int testNumber, InputReader in, PrintWriter out) {

            int n = in.readInt(), m = in.readInt();
            long k = in.readInt();
            long[] a = new long[n + 1], b = new long[m + 1];

            for (int i = 0; i < n; i++)
                a[i + 1] = in.readLong() + a[i];

            for (int i = 0; i < m; i++)
                b[i + 1] = in.readLong() + b[i];

//        System.out.println(Arrays.toString(a));
//        System.out.println(Arrays.toString(b));

            int ans = 0;
            for (int i = 0, j = m; i <= n; i++) {
                if (a[i] > k)
                    break;

                while (a[i] + b[j] > k)
                    j--;

                ans = Math.max(ans, i + j);
            }

            System.out.println(ans);

        }

    }

    static class InputReader {
        private InputStream stream;
        private byte[] buf = new byte[1024];
        private int curChar;
        private int numChars;

        public InputReader(InputStream stream) {
            this.stream = stream;
        }

        public int read() {
            if (numChars == -1)
                throw new RuntimeException();
            if (curChar >= numChars) {
                curChar = 0;
                try {
                    numChars = stream.read(buf);
                } catch (IOException e) {
                    throw new RuntimeException();
                }
                if (numChars <= 0)
                    return -1;
            }
            return buf[curChar++];
        }

        public int readInt() {
            int c = read();
            while (isSpaceChar(c))
                c = read();
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = read();
            }
            int res = 0;
            do {
                res *= 10;
                res += c - '0';
                c = read();
            } while (!isSpaceChar(c));
            return res * sgn;
        }

        public long readLong() {
            int c = read();
            while (isSpaceChar(c))
                c = read();
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = read();
            }
            long res = 0;
            do {
                res *= 10;
                res += c - '0';
                c = read();
            } while (!isSpaceChar(c));
            return res * sgn;
        }

        public boolean isSpaceChar(int c) {
            return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
        }

    }
}



Measured memory_bytes: 38764