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

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

for _ in range(N):
    b, c = map(int, input().split())
    slime[c].append(b)

ans = 0

for v in slime.values():
    cnt = Counter(v)
    ans += sum(cnt.values())-max(cnt.values())

print(ans)