Submission #1024243

---

Source Code Expand

if !ENV['RUBY_THREAD_VM_STACK_SIZE']
  exec({'RUBY_THREAD_VM_STACK_SIZE'=>'1000000000'}, '/usr/bin/ruby', $0)
end

def read_numbers; gets.split.map(&:to_i); end
H, W = read_numbers.map{|i| i+2}
M = 1000000007
MAP = 
  Array.new(W, 0) +
  (H-2).times.flat_map{ [0] + read_numbers + [0] } +
  Array.new(W, 0)
ANS = Array.new(W*H)
DIRS = [+1, -1, +W, -W]
 
$ans = 0
def calc(pos)
  ret = 1

  i = 0
  v = MAP[pos]
  while i < 4
    d = DIRS[i]
    if v < MAP[pos+d]
      plus = ANS[pos+d] || calc(pos+d)
      ret += plus
    end
    i += 1
  end

  ret %= M
  ANS[pos] = ret; $ans += ret
  return ret
end
 
(H-2).times do |y|
  (W-2).times do |x|
    pos = W+1 + y*W+x
    calc(pos) unless ANS[pos]
  end
end
 
p $ans % M

Submission Info

Judge Result