import sys
import math
input = sys.stdin.readline

for _ in range(int(input())):
    n, k = [int(i) for i in input().split()]
    a = [int(i) for i in input().split()]
    max_ = max(a)
    mex_ = [int(i) for i in range(n) if i not in a]
    if len(mex_) > 0:
        res = min(mex_)
    else:
        res = 0
    ans = int(math.ceil(max_ + res) / 2)
    for i in range(k):
        a.append(ans)
    print(len(set(a)))