ns = gets.chomp
if ns.include?(' ')
    ab = ns.split.map(&:to_i).inject(:+)
    s = gets.chomp
    puts "#{ab} #{s}"
    exit
end

if /^[0-9]+$/.match(ns)
    N = ns.to_i
    lines = readlines
    if lines.size == 0
        puts N*(N+1)/2
    elsif lines.size == 1
        puts lines[0].split.map(&:to_i).inject(:+)
    else
        puts lines.map(&:to_i).inject(:+)
    end
else
    puts "Hello World!"
end