from collections import defaultdict

N, M = map(int, input().split())
A = list(map(int, input().split()))
dic = defaultdict(int)
for a in A:
    dic[a % M] += 1
    dic[M - a % M] += 0
ans = 0
for k, v in dic.items():
    if k == 0:
        ans += min(1, dic[k])
    elif k == M // 2:
        if M % 2 == 0:
            ans += min(1, dic[k])
        else:
            ans += max(dic[k], dic[M - k])
    elif k < M//2:
        ans += max(dic[k], dic[M - k])
if ans == 0:
    ans = 1
print(ans)