Chess board tour

n, m = map(int, input().split())
ans = []

if n % 2 == 1 and m % 2 == 1:
    ans.append(-1)

elif m % 2 == 0:
    maxi = m // 2
    for i in range(maxi):
        if i == 0:
            ans.append((n - 1) * "D")
        else:
            ans.append((n - 2) * "D")

        ans += "R"

        ans.append((n - 2) * "U")

        if i == maxi - 1:
            ans.append("U")
        else:
            ans.append("R")

    ans.append("L" * (m - 1))

else:
    maxi = n // 2
    for i in range(maxi):
        if i == 0:
            ans.append((m - 1) * "R")
        else:
            ans.append((m - 2) * "R")

        ans += "D"

        ans.append((m - 2) * "L")

        if i == maxi - 1:
            ans.append("L")
        else:
            ans.append("D")

    ans.append("U" * (n - 1))

print("".join(ans))

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 45, in <module>
    print(...

Test 7

Verdict: ACCEPTED

Test 8

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 45, in <module>
    print(...

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 45, in <module>
    print(...

Test 12

Verdict: ACCEPTED

Test 13

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 45, in <module>
    print(...

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED

Test 16

Verdict: ACCEPTED

Test 17

Verdict: ACCEPTED

Test 18

Verdict: ACCEPTED

Test 19

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 45, in <module>
    print(...

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: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 45, in <module>
    print(...

Test 32

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 45, in <module>
    print(...

Test 33

Verdict: ACCEPTED

Test 34

Verdict: ACCEPTED

Test 35

Verdict: ACCEPTED

Test 36

Verdict: ACCEPTED

Test 37

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 45, in <module>
    print(...

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: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 45, in <module>
    print(...

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: RUNTIME ERROR

Traceback (most recent call last):
  File "input/code.py", line 45, in <module>
    print(...

Test 53

Verdict: ACCEPTED

Test 54

Verdict: ACCEPTED

Test 55

Verdict: ACCEPTED

Test 56

Verdict: ACCEPTED