Problem:
Score: 100 points

Problem Statement

There is a train going from Station A to Station B that costs X yen (the currency of Japan).

Also, there is a bus going from Station B to Station C that costs Y yen.

Joisino got a special ticket. With this ticket, she can take the bus for half the fare if she travels from Station A to Station B by train and then travels from Station B to Station C by bus.

How much does it cost to travel from Station A to Station C if she uses this ticket?

Constraints

1 \leq X,Y \leq 100

Y is an even number.

All values in input are integers.

Input

Input is given from Standard Input in the following format:

X Y

Output

If it costs x yen to travel from Station A to Station C, print x.

Sample Input 1

81 58

Sample Output 1

110

The train fare is 81 yen.

The train fare is 58 ⁄ 2=29 yen with the 50% discount.

Thus, it costs 110 yen to travel from Station A to Station C.

Sample Input 2

4 54

Sample Output 2

31

Solution in Ruby (2.3.3) (judge verdict: Runtime Error)

n,m=STDIN.gets.chomp.split(/ +/).map(&:to_i)
prefs = {}
m.times do |i|
  p,y=STDIN.gets.chomp.split(/ +/).map(&:to_i)
  if prefs[p] == nil
    prefs[p] = []
  end
  prefs[p] << [i,y]
end

prefs.each_value do  |pref|
  pref.sort!{ |a,b| a[1] <=> b[1] }
  pref.each_with_index{ |x,i| x[1]=i + 1 }
end

cities= []

prefs.each do |pref,value|
  value.each do |v|
    cities << [ v[0], pref, v[1] ]
  end
end

cities.sort!{|a,b| a[0]<=>b[0]}

cities.each do |city|
  puts "%06d%06d" % [city[1],city[2]]
end