AtCoder ABC #116 - C Grand Garden

abc116-c.rb

n = gets.chomp.to_i
h = gets.chomp.split(" ").map(&:to_i)
ans = 0
cnt = 0
while true
  n.times do |i|
    if h[i] > 0
      cnt += 1
      h[i] -= 1
    else
      if cnt != 0
        ans += 1
        cnt = 0
      end
    end
  end
  ans += 1 if cnt != 0
  cnt = 0
  break if h.all?{|x| x == 0}
end
puts ans