gets.to_i a = gets.split.map(&:to_i).uniq.sort ans = 0 a.each do |number| if ans != number puts ans exit end ans += 1 end puts ans n, k = gets.split.map(&:to_i) a = gets.split.map(&:to_i) b = gets.split.map(&:to_i) dp = Array.new(2) { Array.new(n, false) } dp[0][0] = true dp[1][0] = true 1.upto(n - 1) do |i| if dp[0][i - 1] dp[0][i] = true if (a[i] - a[i - 1]).abs <= k dp[1][i] = true if (b[i] - a