t=int(input())
for case in range(t): 
    n,k,m = map(int, input().split())
    jg = list(map(int,input().split()))
    jg.sort()
    sum = 0
    for i in range(k):
        sum += jg[i]
    if (sum - n) > 0:
        print (sum - n)
    else:
        print (0)