import java.util.Scanner;

public class Solution {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        int g = sc.nextInt();
        for (int tc = 0; tc < g; tc++) {
            int n = sc.nextInt();
            int m = sc.nextInt();
            int x = sc.nextInt();
            int[] a = readArray(sc, n);
            int[] b = readArray(sc, m);

            System.out.println(solve(a, b, x));
        }

        sc.close();
    }

    static int[] readArray(Scanner sc, int size) {
        int[] result = new int[size];
        for (int i = 0; i < result.length; i++) {
            result[i] = sc.nextInt();
        }
        return result;
    }

    static int solve(int[] a, int[] b, int x) {
        int lengthB = 0;
        int sum = 0;
        while (lengthB < b.length && sum + b[lengthB] <= x) {
            sum += b[lengthB];
            lengthB++;
        }

        int maxScore = lengthB;
        for (int lengthA = 1; lengthA <= a.length; lengthA++) {
            sum += a[lengthA - 1];

            while (sum > x && lengthB > 0) {
                lengthB--;
                sum -= b[lengthB];
            }

            if (sum > x) {
                break;
            }

            maxScore = Math.max(maxScore, lengthA + lengthB);
        }
        return maxScore;
    }
}