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

void main(){
  long a, b;
  readf("%d %d", &a, &b);

  long[] xs = [a, b, a-1, b-1];
  xs = sort(xs).array;

  writeln(xs[$-1] + xs[$-2]);
}
