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#include <bits/stdc++.h>
using namespace std;
#define all(x) (x).begin(), (x).end()
#define mp make_pair
#define fi first

#define se second
#define pb push_back
#define IOS ios_base::sync_with_stdio(0), cin.tie(0)
const int INF = 1001001001;
const int MAXN = 100'000;
const char br = '\n';
using ll = long long;
using vi = vector<int>;
using pii = pair<int, int>;

// === Debug macro starts here ===

int recur_depth = 0;
#ifdef DEBUG
#define dbg(x)                                                                 \
	{                                                                      \
		++recur_depth;                                                 \
		auto x_ = x;                                                   \
		--recur_depth;                                                 \
		cerr << string(recur_depth, '\t') << "\e[91m" << __func__      \
		     << ":" << __LINE__ << "\t" << #x << " = " << x_           \
		     << "\e[39m" << endl;                                      \
	}
#else
#define dbg(x)
#endif
template <typename Ostream, typename Cont>
typename enable_if<is_same<Ostream, ostream>::value, Ostream &>::type
operator<<(Ostream &os, const Cont &v) {
    os << "[";
    for (auto &x : v) {
        os << x << ", ";
    }
    return os << "]";
}

// === Debug macro ends here ===

// print pair, vector
template <typename Ostream, typename... Ts>
Ostream &operator<<(Ostream &os, const pair<Ts...> &p) {
    return os << "{" << p.first << ", " << p.second << "}";
}
template <typename T> ostream &operator<<(ostream &s, vector<T> t) {
    for (const T &v : t) {
        cout << v << " ";
    }
    return s;
}

int nxt() {
    int x;
    cin >> x;
    return x;
}

int main() {
    IOS;

    int n = nxt();
    int m = nxt();


    if (n % 2 == 1 && m % 2 == 1) {
        cout << "-1" << br;
        return 0;
    }

    if (n % 2 == 0) {


        for (int i = 0; i < n - 1; i++) {
            cout << "D";
        }


        int j = 1;
        for (int i = n; i > 1; i -= 2) {
            while (j != m) {
                j++;
                cout << "R";
            }
            cout << "U";
            while (i != 2 && j != 2) {
                j--;
                cout << "L";
            }
            if (i != 2)
                cout << "U";
        }
        for (int i = m; i > 1; i--)
            cout << "L";

    } else {

        for (int i = 0; i < m - 1; i++) {
            cout << "R";
        }


        int j = 1;
        for (int i = m; i > 1; i -= 2) {
            while (j != n) {
                j++;
                cout << "D";
            }
            cout << "L";
            while (i != 2 && j != 2) {
                j--;
                cout << "U";
            }
            if (i != 2)
                cout << "L";
        }
        for (int i = n; i > 1; i--) 
            cout << "U";
    }

    return 0;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED

Test 16

Verdict: ACCEPTED

Test 17

Verdict: ACCEPTED

Test 18

Verdict: ACCEPTED

Test 19

Verdict: ACCEPTED

Test 20

Verdict: ACCEPTED

Test 21

Verdict: ACCEPTED

Test 22

Verdict: ACCEPTED

Test 23

Verdict: ACCEPTED

Test 24

Verdict: ACCEPTED

Test 25

Verdict: ACCEPTED

Test 26

Verdict: ACCEPTED

Test 27

Verdict: ACCEPTED

Test 28

Verdict: ACCEPTED

Test 29

Verdict: ACCEPTED

Test 30

Verdict: ACCEPTED

Test 31

Verdict: ACCEPTED

Test 32

Verdict: ACCEPTED

Test 33

Verdict: ACCEPTED

Test 34

Verdict: ACCEPTED

Test 35

Verdict: ACCEPTED

Test 36

Verdict: ACCEPTED

Test 37

Verdict: ACCEPTED

Test 38

Verdict: ACCEPTED

Test 39

Verdict: ACCEPTED

Test 40

Verdict: ACCEPTED

Test 41

Verdict: ACCEPTED

Test 42

Verdict: ACCEPTED

Test 43

Verdict: ACCEPTED

Test 44

Verdict: ACCEPTED

Test 45

Verdict: ACCEPTED

Test 46

Verdict: ACCEPTED

Test 47

Verdict: ACCEPTED

Test 48

Verdict: ACCEPTED

Test 49

Verdict: ACCEPTED

Test 50

Verdict: ACCEPTED

Test 51

Verdict: ACCEPTED

Test 52

Verdict: ACCEPTED

Test 53

Verdict: ACCEPTED

Test 54

Verdict: ACCEPTED

Test 55

Verdict: ACCEPTED

Test 56

Verdict: ACCEPTED