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


D = {}

for i in range(N):
    if A[i] % M not in D:
        D[A[i] % M] = 0
    D[A[i] % M] += 1
        
ans = 0

S = set()
for k,v in D.items():
    if k == M-k:
        ans += 1
    elif k == 0:
        ans += 1
    else:
        if k not in S:
            if M-k in D:
                ans += max(D[k],D[M-k])
                S.add(M-k)
            else:
                ans += D[k]
                
print(ans)
#print(D)