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;
    }
}

def twoStacks(maxSum, a, b):
    # Write your code here
    i = j = s = 0
    
    while i < len(a) and s + a[i] <= maxSum: 
        s += a[i]
        i += 1
        
    n = maxn = i
    i -= 1
    
    while j < len(b):
        if s + b[j] <= maxSum:
            s += b[j]
            j += 1
            n += 1
            maxn = max(maxn, n)
        elif i >= 0:
               s -= a[i]
               i -= 1
               n -= 1
        else:
            break
    
    return maxn

def twoStacks(maxSum, a, b):
    Totalsum = 0
    countS1 = 0 
    countS2 = 0
    result = 0
    for ele in a:
        if Totalsum + ele > maxSum:
            break
        Totalsum = Totalsum + ele
        countS1 = countS1 + 1
    for ele in b:
        Totalsum = Totalsum + ele
        countS2 = countS2 + 1
        while Totalsum > maxSum and countS1 > 0:
            Totalsum = Totalsum - a[countS1-1]
            countS1 = countS1 -1
        if Totalsum <= maxSum:
            result = max((countS1 + countS2), result)
    return result