flag=-1
a=[]
def printShortestPath(n, i_s, j_s, i_e, j_e):
    if(abs(i_s-i_e)%2==1):
        global flag
        flag=1
        print("Impossible")
    else:
        if(i_s!=i_e or j_s!=j_e):
            if(i_s==i_e):
                if(abs(j_e-j_s)==1):
                    #global flag
                    flag=1
                    print("Impossible")
                elif(j_e<j_s):
                    a.append("L")
                    printShortestPath(n, i_s, j_s-2, i_e, j_e)
                else:
                    a.append("R")
                    printShortestPath(n, i_s, j_s+2, i_e, j_e)    
            elif(i_e<i_s):
                if(j_e<j_s):
                    a.append("UL")
                    printShortestPath(n, i_s-2, j_s-1, i_e, j_e)
                else:
                    a.append("UR")
                    printShortestPath(n, i_s-2, j_s+1, i_e, j_e)
            else:
                if(j_e<j_s):
                    a.append("LL")
                    printShortestPath(n, i_s+2, j_s-1, i_e, j_e)
                else:
                    a.append("LR")
                    printShortestPath(n, i_s+2, j_s+1, i_e, j_e)

if __name__ == "__main__":
    n = int(input().strip())
    i_start, j_start, i_end, j_end = input().strip().split(' ')
    i_start, j_start, i_end, j_end = [int(i_start), int(j_start), int(i_end), int(j_end)]
    printShortestPath(n, i_start, j_start, i_end, j_end)
    if(flag!=1):
        print(len(a))
        for e in a:
            print(e,end=' ')