from collections import defaultdict
n,m=map(int,input().split())
a=list(map(lambda x : int(x) % m,input().split()))
d=defaultdict(int)
for b in a:
    d[b]+=1
    d[m-b]
ans=0
zero=0
onaji=0
for k in d.keys():
    if k==0:
        zero=1
    elif k+k==m:
        onaji=1
    else:
        ans+=max(d[k],d[m-k])
    d[k]=0
    d[m-k]=0
print(ans+zero+onaji)