init project

app/models/challenge_answer.rb

@@ -0,0 +1,11 @@
+class ChallengeAnswer < ApplicationRecord
+  default_scope { order("challenge_answers.level asc") }
+  belongs_to :challenge
+  has_many :game_answers, :dependent => :destroy
+
+  validates :contents, length: { maximum: 25000 , too_long: "不能超过25000个字符"}
+
+  def view_answer_time(user_id)
+    game_answers.where(user_id: user_id).last&.view_time
+  end
+end