h, w = gets.split.map(&:to_i)
memo = [nil] * h
h.times{|i| memo[i] = [false] * w}
ls = []
h.times {|i|
  s = gets.split.map(&:to_i)
  w.times {|j|
    if s[j] == 1
      memo[i][j] = true
      ls << [i, j]
    end
  }
}
ans = 0
ls.each do |i, j|
  next unless memo[i][j]
  ans += 1
  s = [[i, j]]
  while s.size > 0
    i, j = s.pop
    next unless memo[i][j]
    memo[i][j] = false
    s << [i+1, j] if i < h-1
    # s << [i-1, j] if i > 0
    s << [i, j+1] if j < w-1
    s << [i, j-1] if j > 0
  end
end
p ans