function Main(input){
  input = input.split("\n");
  inputStr = input[0].split(" ");
  var L = Number.parseInt(inputStr[0]);
  var R = Number.parseInt(inputStr[1]);
  var arr = [];
  var min = 2019;  
  if ( L * R > 2019){
    for(var i1 = L; i1 < R; i1++){
      for(var i2 = L+1 ; i2 < R+1; i2++){
        var tmp = (i1 * i2) % 2019;
        if(tmp === 0){
          //console.log(0);
          min = tmp;
          break;
        } else {
          min = tmp < min ? tmp : min;
        }
      }
    }
	console.log(min);
  } else {
    //LとRの積が2019を超えないなら計算する必要がない
    console.log(L * (L+1));
  }
}
Main(require("fs").readFileSync("/dev/stdin", "utf8"));