import sys

class Node:
    def __init__(self, data, next = None):
        self.data = data
        self.next = next
        
class Stack:
    def __init__(self):
        self.top = None
    
    def isempty(self):
        if self.top is None:
            return True
        return False
    
    def peek(self):
        if not self.isempty():
            return self.top.data
        return 0
    
    def push(self, data):
        node = Node(data)
        if self.isempty():
            self.top = node
            return
        node.next = self.top
        self.top = node
        
    def pop(self):
        if self.isempty():
            raise Exception("Stack Overflow")
        data = self.top.data
        self.top = self.top.next
        return data

if __name__ == '__main__': 
    g = int(input())

    for g_itr in range(g):
        nmx = input().split()

        n = int(nmx[0])

        m = int(nmx[1])

        x = int(nmx[2])

        ni = sys.stdin.readline().strip().split()
        mi = sys.stdin.readline().strip().split()
        stack1, stack2 = Stack(), Stack()
        for i in range(n-1, -1, -1):
            stack1.push(int(ni[i]))

        for i in range(m-1,-1,-1):
            stack2.push(int(mi[i]))

        live_sum, i, j = 0, 0, 0
        junk = Stack()
        while not stack1.isempty() and live_sum + stack1.peek() <= x:
            live_sum += stack1.peek()
            junk.push(stack1.pop())
            i += 1
        count = i
        while not stack2.isempty():
            live_sum += stack2.pop()
            j += 1
            while live_sum>x and not junk.isempty():
                i-=1
                live_sum -= junk.pop()
            if live_sum<=x and i+j>count:
                count = i+j

        result = count
        print(result)