from collections import defaultdict
N, M = map(int, input().split())
A = list(map(int, input().split()))

d = defaultdict(int)
for a in A:
    d[a % M] += 1

ans = 0
used = set()
for k in list(d.keys()):
    kk = (M - k) % M
    if k in used:
        continue
    if kk in used:
        continue
    if k == kk:
        ans += min(1, d[k])
        used.add(k)
    else:
        ans += max(d[k], d[kk])
        used.add(k)
        used.add(kk)

print(ans)