from itertools import product
n, k = list(map(int, list(input().split())))
m = []
#n = int(input())
for i in range(n):
    m.append(list(map(int, (input().split()[1:]))))

combinations = list(product(*m))

squared_m = []
semifinal_list = []

for combination in combinations:
    tuples = ()
    for i in combination:
        tuples += (i**2),
    squared_m.append(tuples)
for i in squared_m:
    semifinal_list.append(sum(i)%k)

print(max(semifinal_list))