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#include <iostream>
#include <vector>
#include <string>
using namespace std;

string generateHamiltonianPath(int n, int m) {
    // Impossible case where both dimensions are odd
    if ((n % 2 != 0) && (m % 2 != 0)) {
        return "-1";
    }

    string path;
    if (n % 2 == 0) {
        // n is even, process row-wise
        for (int row = 1; row <= n; ++row) {
            if (row % 2 == 1) { // Odd row: move right
                path += string(m - 1, 'R');
            } else { // Even row: move left
                path += string(m - 1, 'L');
            }
            if (row != n) {
                path += 'D'; // Move down except on the last row
            }
        }
        // Return path to start
        for (int i = 1; i < n; ++i) {
            path += 'U';
        }
    } else if (m % 2 == 0) {
        // m is even, process column-wise
        for (int col = 1; col <= m; ++col) {
            if (col % 2 == 1) { // Odd column: move down
                path += string(n - 1, 'D');
            } else { // Even column: move up
                path += string(n - 1, 'U');
            }
            if (col != m) {
                path += 'R'; // Move right except on the last column
            }
        }
        // Return path to start
        for (int i = 1; i < m; ++i) {
            path += 'L';
        }
    }
    return path;
}

int main() {
    int n, m;
    cin >> n >> m;
    string result = generateHamiltonianPath(n, m);
    if (result != "-1") {
        cout << result << endl;
    } else {
        cout << "-1" << endl;
    }
    return 0;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: WRONG ANSWER

Test 6

Verdict: ACCEPTED

Test 7

Verdict: WRONG ANSWER

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: WRONG ANSWER

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: WRONG ANSWER

Test 18

Verdict: WRONG ANSWER

Test 19

Verdict: ACCEPTED

Test 20

Verdict: WRONG ANSWER

Test 21

Verdict: WRONG ANSWER

Test 22

Verdict: ACCEPTED

Test 23

Verdict: WRONG ANSWER

Test 24

Verdict: ACCEPTED

Test 25

Verdict: ACCEPTED

Test 26

Verdict: ACCEPTED

Test 27

Verdict: WRONG ANSWER

Test 28

Verdict: WRONG ANSWER

Test 29

Verdict: WRONG ANSWER

Test 30

Verdict: WRONG ANSWER

Test 31

Verdict: ACCEPTED

Test 32

Verdict: ACCEPTED

Test 33

Verdict: WRONG ANSWER

Test 34

Verdict: WRONG ANSWER

Test 35

Verdict: WRONG ANSWER

Test 36

Verdict: WRONG ANSWER

Test 37

Verdict: ACCEPTED

Test 38

Verdict: WRONG ANSWER

Test 39

Verdict: WRONG ANSWER

Test 40

Verdict: WRONG ANSWER

Test 41

Verdict: WRONG ANSWER

Test 42

Verdict: WRONG ANSWER

Test 43

Verdict: WRONG ANSWER

Test 44

Verdict: ACCEPTED

Test 45

Verdict: WRONG ANSWER

Test 46

Verdict: WRONG ANSWER

Test 47

Verdict: WRONG ANSWER

Test 48

Verdict: WRONG ANSWER

Test 49

Verdict: WRONG ANSWER

Test 50

Verdict: WRONG ANSWER

Test 51

Verdict: WRONG ANSWER

Test 52

Verdict: ACCEPTED

Test 53

Verdict: WRONG ANSWER

Test 54

Verdict: WRONG ANSWER

Test 55

Verdict: WRONG ANSWER

Test 56

Verdict: WRONG ANSWER