https://www.lanqiao.cn/problems/602/learning/?page=1&first_category_id=1&name=%E8%BF%B7%E5%AE%AB

#include <bits/stdc++.h>
#define int long long
#define xx first
#define yy second
using namespace std;
const int N = 110;
typedef pair<int , int> PII;
queue<PII> q;    
int n, m, a, b, c, h;
char g[N][N]; 
char path[4] = {'D','L','R','U'};
string path_str[50][50];
int d[N][N]; 

int bfs() {
    memset(d, -1, sizeof(d));  
    d[1][1] = 0;
    int dx[4] = {1,0,0,-1}, dy[4] = {0,-1,1,0 }; 


    while (q.size()) {
        auto t = q.front();
        q.pop();

        for (int i = 0; i < 4; i++) {
            int x = t.first + dx[i];
            int y = t.second + dy[i];
            if (x >= 1 && x <= n && y >= 1 && y <= m && g[x][y] == '0' && d[x][y] == -1) {
                d[x][y] = d[t.xx][t.yy] + 1; 
                q.push({x, y}); 
                path_str[x][y] = path_str[t.first][t.second] + path[i];
                if (x == n && m == y) return d[x][y];
            }
        }
    }
    return -1;
}

void solve() {
    cin>>n>>m;
    for (int i = 1; i <= n; i++)
    for (int j = 1; j <= m; j++)
    cin >> g[i][j];
     q.push({1,1});
     bfs();
    cout<<path_str[n][m]<<endl;


}


signed main() {
    int t = 1;
     //cin >> t;
      //while (t--) solve();
   cout<<"DDDDRRURRRRRRDRRRRDDDLDDRDDDDDDDDDDDDRDDRRRURRUURRDDDDRDRRRRRRDRRURRDDDRRRRUURUUUUUUULULLUUUURRRRUULLLUUUULLUUULUURRURRURURRRDDRRRRRDDRRDDLLLDDRRDDRDDLDDDLLDDLLLDLDDDLDDRRRRRRRRRDDDDDDRR"<<endl;
    return 0;
} [](http://)