from collections import defaultdict, Counter
dic = defaultdict(list)
N, M = map(int, input().split())
BC = [list(map(int, input().split())) for _ in range(N)]
for b, c in BC:
    dic[c].append(b)
ans = 0
for k, v in dic.items():
    n = len(v)
    L = list(Counter(v).items())
    L.sort(key = lambda x:-x[1])
    ans += n - L[0][1]
print(ans)