import std.stdio, std.conv, std.string, std.range, std.algorithm, std.array, std.functional;

void main() {
  auto S = readln.chomp;

  auto res = true;
  foreach(i, c; S) {
    auto odd = i % 2;
    if(!odd && !c.among('R', 'U', 'D')) res = false;
    if(odd && !c.among('L', 'U', 'D')) res = false;
  }

  writeln(res ? "Yes" : "No");
}
