function Main(input) {
  var inp = input.split(" ");
  var a = inp[0];
  var b = inp[1];
  var c = "a" + "b";
  var result = null;
  for (var i = 0; i < 10000; i * i) {
    if (i == c) {
      result = 'Yes';
    } else {
      result = 'No';
    }
  }
  console.log(result);
}
Main(require("fs").readFileSync("/dev/stdin", "utf8"));