n = int(raw_input())

sx, sy, dx, dy = map(int, raw_input().split(' '))

sol = []

if (dx - sx) % 2 != 0:
    print 'Impossible'
else:
    mv = ['LL', 'LR'] if dx > sx else ['UL', 'UR']
    c = abs((dx - sx)/2)
    d = abs(dy - sy) - c
    if d >= 0:
        if d % 2 != 0:
            print 'Impossible'
        else:
            if dy < sy:
                sol += [mv[0]] * c
                sol += ['L'] * int(d / 2)
            else:
                sol += [mv[1]] * c
                sol += ['R'] * int(d / 2)
    else:
        x = c - abs(dy - sy)
        if x % 2 != 0:
            print 'Impossible'
        else:
            x /= 2
            if dy > sy:
                sol += [mv[1]] * (c - x)
                sol += [mv[0]] * x
            else:
                sol += [mv[0]] * (c - x)
                sol += [mv[1]] * x
if sol:
    m = {
        'UL': 1, 'UR': 2, 'R': 3, 'LR' : 4, 'LL': 5, 'L': 6
    }
    sol = sorted(sol, key=lambda x: m[x])
    print len(sol)
    print ' '.join(sol)