#include <iostream>
#include <string>
#include <vector>
#include <queue>
#include <tuple>
#include <array>
#include <map>
#include <boost/algorithm/string.hpp>
#include <boost/unordered_set.hpp>

using namespace std;

typedef vector<char> TableRow;
typedef vector<TableRow> Table;

struct Board {
  Table sData, dData;
  int px, py;

  Board(string b) {
    vector<string> data;
    boost::split(data, b, boost::is_any_of("\n"));

    size_t width = 0;
    for (auto &row: data)
      width = max(width, row.size());

    map<char,char> maps = {{' ',' '}, {'.','.'}, {'@',' '},
                           {'#','#'}, {'$',' '}},
                   mapd = {{' ',' '}, {'.',' '}, {'@','@'},
                           {'#',' '}, {'$','*'}};

    for (size_t r = 0; r < data.size(); r++) {
      TableRow sTemp, dTemp;
      for (size_t c = 0; c < width; c++) {
        char ch = c < data[r].size() ? data[r][c] : ' ';
        sTemp.push_back(maps[ch]);
        dTemp.push_back(mapd[ch]);
        if (ch == '@') {
          px = c;
          py = r;
        }
      }
      sData.push_back(sTemp);
      dData.push_back(dTemp);
    }
  }

  bool move(int x, int y, int dx, int dy, Table &data) {
    if (sData[y+dy][x+dx] == '#' || data[y+dy][x+dx] != ' ')
      return false;

    data[y][x] = ' ';
    data[y+dy][x+dx] = '@';
    return true;
  }

  bool push(int x, int y, int dx, int dy, Table &data) {
    if (sData[y+2*dy][x+2*dx] == '#' || data[y+2*dy][x+2*dx] != ' ')
      return false;

    data[y][x] = ' ';
    data[y+dy][x+dx] = '@';
    data[y+2*dy][x+2*dx] = '*';
    return true;
  }

  bool isSolved(const Table &data) {
    for (size_t r = 0; r < data.size(); r++)
      for (size_t c = 0; c < data[r].size(); c++)
        if ((sData[r][c] == '.') != (data[r][c] == '*'))
          return false;
    return true;
  }

  string solve() {
    boost::unordered_set<Table, boost::hash<Table>> visited;
    visited.insert(dData);

    queue<tuple<Table, string, int, int>> open;
    open.push(make_tuple(dData, "", px, py));

    vector<tuple<int, int, char, char>> dirs = {
        make_tuple( 0, -1, 'u', 'U'),
        make_tuple( 1,  0, 'r', 'R'),
        make_tuple( 0,  1, 'd', 'D'),
        make_tuple(-1,  0, 'l', 'L')
    };

    while (open.size() > 0) {
      Table temp, cur = get<0>(open.front());
      string cSol = get<1>(open.front());
      int x = get<2>(open.front());
      int y = get<3>(open.front());
      open.pop();

      for (int i = 0; i < 4; ++i) {
        temp = cur;
        int dx = get<0>(dirs[i]);
        int dy = get<1>(dirs[i]);

        if (temp[y+dy][x+dx] == '*') {
          if (push(x, y, dx, dy, temp) &&
              visited.find(temp) == visited.end()) {
            if (isSolved(temp))
              return cSol + get<3>(dirs[i]);
            open.push(make_tuple(temp, cSol + get<3>(dirs[i]),
                                 x+dx, y+dy));
            visited.insert(temp);
          }
        } else if (move(x, y, dx, dy, temp) &&
                   visited.find(temp) == visited.end()) {
          if (isSolved(temp))
            return cSol + get<2>(dirs[i]);
          open.push(make_tuple(temp, cSol + get<2>(dirs[i]),
                               x+dx, y+dy));
          visited.insert(temp);
        }
      }
    }

    return "No solution";
  }
};

int main() {
  string level = "#######\n"
                 "#     #\n"
                 "#     #\n"
                 "#. #  #\n"
                 "#. $$ #\n"
                 "#.$$  #\n"
                 "#.#  @#\n"
                 "#######";

  cout << level << endl << endl;
  Board board(level);
  cout << board.solve() << endl;
  return 0;
}