function Main(input){
	inputs = input.trim().split(' ');
	nums = inputs.map(inputs=>parseInt(inputs,10));
    a = nums[0]+(nums[0]-1);
    b = nums[1]+(nums[1]-1);
    c = nums[0]+(nums[1]);
	console.log(Math.max(a, b, c));
}
 
Main(require("fs").readFileSync("/dev/stdin","utf8"));