from collections import defaultdict
N,M = map(int,input().split())
A = list(map(int,input().split()))
seen = defaultdict(bool)
cnt = defaultdict(int)
ans = 0
for a in A:
    cnt[a%M] += 1
keys = list(cnt.keys())
for key in keys:
    if key == 0:
        ans += 1
        continue
    if seen[key]:
        continue
    inv = M - key
    if key == M //2 and M % 2 == 0:
        ans += 1
    else:
        ans += max(cnt[key],cnt[inv])
    seen[key] = True
    seen[inv] = True
print(ans)