N, x, y = gets.split.map(&:to_i) MOD = 998_244_353 if x > y x, y = y, x end x += 1 if x != 1 y -= 1 if y != N d = y - x dp = Array.new(d + 1, 0) dp[0] = 1 1.upto(d) do |i| dp[i] += dp[i - 1] dp[i] += dp[i - 3] if i - 3 >= 0 dp[i] %= MOD end if d < 0 puts 0 else puts dp[d] end