import sys

def solve():
    input = sys.stdin.read
    data = input().split()
    if not data:
        return
    
    H = int(data[0])
    W = int(data[1])
    
    
    idx = 2
    grid = []
    for _ in range(H):
        grid.append([int(x) for x in data[idx:idx+W]])
        idx += W

    
    R = sum(sum(row) % 2 for row in grid)
    C = sum(sum(col) % 2 for col in zip(*grid))

    
    if R % 2 == C % 2:
        ans = max(R, C)
    else:
        ans = max(R, C) + 1

    print(ans)

if __name__ == '__main__':
    solve()