from collections import defaultdict

n,m=list(map(int,input().split()))
seq=list(map(int,input().split()))
cnt=0
am=defaultdict(int)

for i in range(len(seq)):
    sur=seq[i]%m
    am[sur]+=1
    am[m-sur]+=0

if am[0]>0:
    
    cnt+=1
    am[0]=0
if m%2==0:
    if am[int(m/2)]>0:
        cnt+=1
        am[int(m/2)]=0
        
    for i in am.keys():
        if i!=0:
            cnt+=max(am[i],am[m-i])
            am[i]=0
            am[m-i]=0

else:
    for i in am.keys():
        if i!=0:
            cnt+=max(am[i],am[m-i])
            am[i]=0
            am[m-i]=0
    
print(cnt)