All moose are kings of the forest, but your latest moose-friend, Karl-Älgtav, is more interesting than most. In part because of his fondness of fermented blueberries, and in part because of the tribe he lives in. Each year his tribe holds a tournament to determine that year's alphamoose. The winner gets to mate with all the moose-chicks, and then permanently leaves the tribe. The pool of contenders stays constant over the years, apart from the old alpha-moose being replaced by a newcomer in each tournament.
Karl-Älgtav has recently begun to wonder when it will be his turn to win all the chicks, and has asked you to help him determine this. He has supplied a list of the strength of each of the other male moose in his tribe that will compete during the next n - 1 years, along with their time of entry into the tournament. Assuming that the winner each year is the moose with greatest strength, determine when Karl-Älgtav becomes the alpha-moose.
The first line contains two space separated integers k (1 ≤ k ≤ 10^5
) and n (1 ≤ n ≤ 10^5
), denoting the size of the tournament pool and the number of years for which you have been supplied sufficient information.
Next is a single line describing Karl-Älgtav, containing the two integers y (2011 ≤ y ≤ 2011 + n - 1) and p (0 ≤ p ≤ 2^31 - 1
). These are his year of entry into the tournament and his strength, respectively.
Then follow n + k - 2 lines describing each of the other moose, in the same format as for Karl-Älgtav.
Note that exactly k of the moose will have 2011 as their year of entry, and that the remaining n - 1 moose will have unique years of entry.
You may assume that the strength of each moose is unique.
The year Karl-Älgtav wins the tournament, or unknown if the given data is insufficient for determining this.