MOD = 998244353i64
n = read_line.to_i
a = read_line.split.map(&.to_i)
count = Hash(Int32, Int64).new { |h, k| h[k] = 0i64 }
n.times do |i|
  v = a[i]
  count[v] = (count[v] + count[v - 1] + 1) % MOD
end
puts (count.values.sum - n) % MOD