from collections import defaultdict


N, M = map(int, input().split())
A = list(map(int, input().split()))

r = defaultdict(int)
for i in range(N):
    r[A[i] % M] += 1
    if M - (A[i] % M) not in r:
        r[M - (A[i] % M)] = 0

ans = 0
done = set()
if 0 in r:
    ans += 1
    done.add(0)
    done.add(M)
if M % 2 == 0 and (M // 2 in r):
    ans += 1
    done.add(M // 2)

for i in r:
    if i in done:
        continue
    else:
        ans += max(r[i], r[M - i])
        done.add(i)
        done.add(M - i)

print(ans)