import std.stdio, std.conv, std.string, std.algorithm, std.range;
import std.functional;

void main()
{
  auto N = readln.split[0].to!int;
  auto v = readln.split.to!(int[]);

  v.sort!"a<b";

  auto ans = v.length > 0 ? v.reduce!"(a+b)/2" : v[0];
  ans.writeln;
}
