n = STDIN.gets.to_i
t, a = STDIN.gets.split(' ').map(&:to_i)
heights = STDIN.gets.split(' ').map(&:to_i)

diff = 10**10
index = -1

heights.each_with_index do |h, i|
  average_tempurature = t - h * 0.006
  if diff > (a - average_tempurature).abs
    diff = (a - average_tempurature).abs
    index = i
  end
end

puts index + 1
