def main():
    n, stu_num = map(int, input().split())
    res = [list(map(int, input().split())) for _ in range(n)]

    res.sort(key=lambda x:x[1], reverse=True)
    dico = {res[i][0]:i+1 for i in range(len(res))}
    print(dico[stu_num])


for _ in range(int(input())):
    main()