import sys #input = sys.stdin.readline input = sys.stdin.buffer.readline #文字列はダメ #sys.setrecursionlimit(1000000) #import bisect #import itertools #import random #from heapq import heapify, heappop, heappush from collections import defaultdict #from collections import deque #import copy #import math #from functools import lru_cache #@lru_cache(maxsize=None) #MOD = pow(10,9) + 7 #MOD = 998244353 #dx = [1,0,-1,0] #dy = [0,1,0,-1] #dx8 = [1,1,0,-1,-1,-1,0,1] #dy8 = [0,1,1,1,0,-1,-1,-1] def main(): N,M = map(int,input().split()) A = list(map(int,input().split())) dic = defaultdict(int) num = set([]) for a in A: dic[a%M] += 1 num.add(min(a%M, M - a%M)) num = list(num) num.sort() ans = 0 if M%2 == 0: for i in num: if i == 0: ans += min(1, dic[0]) elif i < M//2: ans += max(dic[i], dic[M-i]) else: ans += min(1, dic[M//2]) else: for i in num: if i == 0: ans += min(1, dic[0]) elif i < (M+1)//2: ans += max(dic[i], dic[M-i]) print(ans) if __name__ == '__main__': main()