#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <string>
#include <queue>
#include <map>
#include <vector>
#include <set>
#include <cmath>
#include <iomanip>
#include <algorithm>
#include <stack>

using namespace std;
typedef long long ll;
typedef double db;

vector<int> dx = { 0, 1, 0, -1 };
vector<int> dy = { 1, 0, -1, 0 };
vector<char> dicrets {'D', 'R', 'U', 'L'};

struct Node
{
	int type;
	bool was;
	bool moved;
};

int n, m;
vector<vector<Node>> g;
vector<pair<int, int>> monsters;

bool check_is_exit(int x, int y)
{
	return (x == 0 || y == 0 || x == m - 1 || y == n - 1);
}

bool check_inside(int x, int y)
{
	return (x >= 0 && y >= 0 && x < m && y < n);
}

void move_monster(int direct, bool moving_new_pos)
{
	for (int i = 0; i < monsters.size(); i++)
	{
		if (g[monsters[i].second][monsters[i].first].moved == false && moving_new_pos == false)
		{
			continue;
		}
		int new_y = monsters[i].second + dy[direct];
		int new_x = monsters[i].first + dx[direct];
		if (!check_inside(new_x, new_y))
		{
			continue;
		}
		if (g[new_y][new_x].type == 0)
		{
			if (g[new_y][new_x].moved)
			{
				continue;
			}
		}
		else if (g[new_y][new_x].type == 1)
		{
			continue;
		}
		g[new_y][new_x].moved = moving_new_pos;
		g[monsters[i].second][monsters[i].first].type = 2;

		monsters[i].first = new_x;
		monsters[i].second = new_y;

		g[monsters[i].second][monsters[i].first].type = 0;
	}
}

vector<int> res;

bool dfs(int x, int y)
{
	if (g[y][x].was)
	{
		return false;
	}
	g[y][x].was = true;
	if (check_is_exit(x, y))
	{
		return true;
	}
	for (int i = 0; i < 4; i++)
	{
		//move all monsters
		move_monster(i, true);
		if (g[y + dy[i]][x + dx[i]].type == 2)
		{
			if (dfs(x + dx[i], y + dy[i]))
			{
				res.push_back(i);
				return true;
			}
		}
		// move back
		move_monster((i + 2) % 4, false);
	}
	return false;
}

int main()
{
	cin >> n >> m;
	g.resize(n, vector<Node> (m));
	int start_x = 0;
	int start_y = 0;
	for (int i = 0; i < n; i++)
	{
		for (int j = 0; j < m; j++)
		{
			char c;
			cin >> c;
			if (c == 'A')
			{
				start_y = i;
				start_x = j;
				g[i][j].type = 2;
			}
			else if (c == 'M')
			{
				g[i][j].type = 0;
				monsters.push_back(make_pair(j, i));
			}
			else
			{
				g[i][j].type = ((c == '#') ? 1 : 2);
			}
		}
	}
	if (dfs(start_x, start_y))
	{
		cout << "YES" << endl << res.size() << endl;
		for (int i = res.size() - 1; i >= 0; i--)
		{
			cout << dicrets[res[i]];
		}
	}
	else
	{
		cout << "NO";
	}
}