from collections import defaultdict
n,m = map(int,input().split())
a = list(map(int,input().split()))
a = [num%m for num in a]
if sum(a) == 0:
    print(0)
    exit()

d = defaultdict(int)
db = defaultdict(bool)
for num in a:
    d[num] += 1
    db[num] = True

ans = 0
for num in a:
    if num != 0 and db[num]:
        db[num] = False
        db[m-num] = False
        ans += max(d[num],d[m-num])

if 0 in a:
    ans += 1

print(ans)