from _collections import defaultdict
n,m=map(int,input().split())
s=set()
a=list(map(int,input().split()))
for i in range(n):a[i]%=m
cnt=defaultdict(int)

ans=0
nod=set()

for x in a:
    cnt[x]+=1
for x in cnt:
    nod.add(x)
    nod.add((m-x)%m)

for x in nod:
    y=(m-x)%m
    if y<x:continue
    if x==y:
        ans+=min(1,cnt[x])
        continue
    ans+=max(cnt[x],cnt[y])
print(ans)