#!/usr/bin/python
# -*- coding: UTF-8 -*-
tcase=int(raw_input().strip())
for i in range(tcase):
    n,k,m=map(int,raw_input().strip().split())
    li=[]
    li=map(int,raw_input().strip().split())
    li.sort()
    sum=0
    for j in range(k):
        sum +=li[j]
    if sum >n:
        s=sum-n
    else:
        s=0
    print s