import sys
input = sys.stdin.readline
from collections import defaultdict

N,M=map(int,input().split())
A=list(map(int,input().split()))

cnt=defaultdict(int)
for a in A:
    cnt[a%M]+=1
ans=0
check = set()
if cnt[0]>0:
    ans = 1
if M%2==0 and cnt[M//2]>0:
    ans += 1
    check.add(M//2)
check.add(0)
keys = list(cnt.keys())
for i in keys:
    if i in check:continue
    if cnt[i] >= cnt[M-i]:
        ans += cnt[i]
    else:
        ans += cnt[M-i]
    check.add(i)
    check.add(M-i)


print(ans)