import sys, math
sys.setrecursionlimit(10**8)
sys.set_int_max_str_digits(0)
INF = 10**18
MOD = 998244353
from bisect import bisect_left, bisect_right
from collections import deque, defaultdict, Counter
from itertools import product, combinations, permutations, groupby, accumulate
from heapq import heapify, heappop, heappush

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

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

ans = 0
for k, v in data.items():
    most_common_box_for_this_color = Counter(v).most_common()[0][1]
    #print(k, most_common_box_for_this_color)
    ans += len(v) - most_common_box_for_this_color
print(ans)