#include <bits/stdc++.h>
using namespace std;
using u32 = unsigned;
using i64 = long long;
using u64 = unsigned long long;

int p[25][25]={0};
int gt[25][25]={0};
int X[4]={-1,0,1,0},Y[4]={0,1,0,-1};
char dir[5]="URDL";

void dfs(int x,int y,int from) {
    if(p[x][y]==0||gt[x][y]==1) {
        return;
    }
    if(from!=4) {
        cout<<dir[from];
    }
    gt[x][y]=1;
    for(int i=0;i<4;i++) {
        dfs(x+X[i],y+Y[i],i);
    }
    if(from!=4) {
        cout<<dir[(from+2)%4];
    }
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    
    int n,m;
    int sx,sy;
    cin>>n>>m;
    for(int i=1;i<=n;i++) {
        for(int j=1;j<=m;j++) {
            char c;
            cin>>c;
            p[i][j]=c-'0';
            if(p[i][j]) {
                sx=i,sy=j;
            }
        }
    }
    dfs(sx,sy,4);
    
    return 0;
}