The king is left alone on the chessboard. In spite of this loneliness, he doesn't lose heart, because he has business of national importance. For example, he has to pay an official visit to square *t*. As the king is not in habit of wasting his time, he wants to get from his current position *s* to square *t* in the least number of moves. Help him to do this.

In one move the king can get to the square that has a common side or a common vertex with the square the king is currently in (generally there are 8 different squares he can move to).
The first line contains the chessboard coordinates of square *s*, the second line — of square *t*.

Chessboard coordinates consist of two characters, the first one is a lowercase Latin letter (from a to h), the second one is a digit from 1 to 8.
# citim datele
s = str(input())
s1 = s[:1]
b = int(s[1:])
# am impartit tabla de sah in 8x8
# literi ii atribui valoarea din tabel
if s1 == 'h' : a = 8
if s1 == 'g' : a = 7
if s1 == 'f' : a = 6
if s1 == 'e' : a = 5
if s1 == 'd' : a = 4
if s1 == 'c' : a = 3
if s1 == 'b' : a = 2
if s1 == 'a' : a = 1
# la fel si pentru destinatie
t = str(input())
t1 = t[:1]
b1 = int(t[1:])
if t1 == 'h' : a1 = 8
if t1 == 'g' : a1 = 7
if t1 == 'f' : a1 = 6
if t1 == 'e' : a1 = 5
if t1 == 'd' : a1 = 4
if t1 == 'c' : a1 = 3
if t1 == 'b' : a1 = 2
if t1 == 'a' : a1 = 1
'''
print(a)
print(a1)
print(b)
print(b1)
'''
# aceiasi functie ca sii pentru afisarea miscarilor
# doar ca aici le numaram, si nu le afisam
def countthemerges(a,b,a1,b1):
    q = 0
    c = True
    while(c):

        if a < a1 and b > b1 :
            a = a + 1
            b = b - 1
            q+=1


        if a > a1 and b > b1:
            a = a -1
            b = b -1
            q+=1

        if a < a1 and b < b1:
            a = a +1
            b = b +1
            q+=1

        if a > a1 and b < b1 :
            a = a -1
            b = b +1
            q+=1

        if a == a1 and b > b1:
            b = b - 1
            q+=1

        if a == a1 and b < b1 :
            b = b + 1
            q+=1

        if b == b1 and a1 > a :
            a = a + 1
            q+=1

        if b == b1 and a > a1 :
            a = a - 1
            q+=1


        if a == a1 and  b1 == b :
            return q

# functie pentru afisarea miscarilor
def printthePosibitities(a,b,a1,b1):
    # iteram pana cand a e diferit de a1 si b de b1
    # algoritm de logica si matematica usoara
    # incrementam sau derementam valorile lui a si b
    # pana cand ele nu sunt egale cu a1 si b1
    # si respectiv la fiecare manipulare matimatica
    # afisam miscarea necesara
    c = True
    while(c):
        if a < a1 and b > b1 :
            print('RD')
            a = a + 1
            b = b - 1

        if a > a1 and b > b1:
            print('LD')
            a = a -1
            b = b -1

        if a < a1 and b < b1:
            print('RU')
            a = a +1
            b = b +1

        if a > a1 and b < b1 :
            print('LU')
            a = a -1
            b = b +1

        if a == a1 and b > b1:
            print('D')
            b = b - 1

        if a == a1 and b < b1 :
            print('U')
            b = b + 1

        if b == b1 and a1 > a :
            print('R')
            a = a + 1

        if b == b1 and a > a1 :
            print('L')
            a = a - 1

        if a == a1 and  b1 == b :
            c =False

# afisam numarul total de miscari
print(countthemerges(a,b,a1,b1))
# afisam miscarile
printthePosibitities(a,b,a1,b1)
