'use strict'
function Main(input){
  input=input.trim().split(/\s+/).map(x=>x-0);
  var A=input.shift();
  var B=input.shift();
  var result=Math.max(2*A-1,2*B-1,A+B);
  console.log(result);
}

Main(require('fs').readFileSync('/dev/stdin','utf8'));