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