function main(input) {
  var A = input.split(" ").map(i => parseInt(i))[0];
  var B = input.split(" ").map(i => parseInt(i))[0];
  var max = 0;
  if (max < A + A - 1) {
    max = A + A - 1;
  }
  if (max < A + B) {
    max = A + B - 1;
  }
  if (max < B + B - 1) {
    max = B + B - 1;
  }
  console.log(max);
}
main(require('fs').readFileSync('/dev/stdin', 'utf8'));