H, W = map(int, input().split())
A = [list(map(int, input().split())) for _ in range(H)]

ans1 = 0
for i in range(H):
    ans1 += sum(A[i])%2
ans2 = 0
for i in range(W):
    ans2 += sum(A[j][i] for j in range(H))%2

print(max(ans1, ans2))