H,W = map(int,input().split())

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

ans1 = 0
for i in range(H):
    res = 0
    for j in range(W):
        res ^= A[i][j]
    if res == 1:
        ans1 += 1


ans2 = 0
for j in range(W):
    res = 0
    for i in range(H):
        res ^= A[i][j]
    if res == 1:
        ans2 += 1

print(max(ans1,ans2))