N = int(eval(input()))

S = eval(input())



for lf in ['SS','SW','WS','WW']:

    tmp = lf

    for c in S:

        if (tmp[-1]=='W') ^ (c=='x'):

            t = 'S' if tmp[-2]=='W' else 'W'

        else:

            t = 'S' if tmp[-2]=='S' else 'W'

        tmp += t

    if tmp[:2] == tmp[-2:]:

        print((tmp[1:-1]))

        exit()

print((-1))
N = int(eval(input()))

S = eval(input())



for a,b in ['SS','SW','WS','WW']:

    tmp = a+b

    for c in S:

        if (c=='x') ^ (tmp[-1]=='W'):

            tmp += ('W' if tmp[-2]=='S' else 'S')

        else:

            tmp += tmp[-2]

    #print(tmp)

    if tmp[:2] == tmp[-2:]:

        print((tmp[1:-1]))

        exit()

print((-1))
N = int(eval(input()))
S = eval(input())
for lf in ["SS", "SW", "WS", "WW"]:
    tmp = lf
    for c in S:
        if (tmp[-1] == "W") ^ (c == "x"):
            t = "S" if tmp[-2] == "W" else "W"
        else:
            t = "S" if tmp[-2] == "S" else "W"
        tmp += t
    if tmp[:2] == tmp[-2:]:
        print((tmp[1:-1]))
        exit()
print((-1))

N = int(eval(input()))
S = eval(input())
for a, b in ["SS", "SW", "WS", "WW"]:
    tmp = a + b
    for c in S:
        if (c == "x") ^ (tmp[-1] == "W"):
            tmp += "W" if tmp[-2] == "S" else "S"
        else:
            tmp += tmp[-2]
    # print(tmp)
    if tmp[:2] == tmp[-2:]:
        print((tmp[1:-1]))
        exit()
print((-1))

-for lf in ["SS", "SW", "WS", "WW"]: -    tmp = lf +for a, b in ["SS", "SW", "WS", "WW"]: +    tmp = a + b -        if (tmp[-1] == "W") ^ (c == "x"): -            t = "S" if tmp[-2] == "W" else "W" +        if (c == "x") ^ (tmp[-1] == "W"): +            tmp += "W" if tmp[-2] == "S" else "S" -            t = "S" if tmp[-2] == "S" else "W" -        tmp += t +            tmp += tmp[-2] +    # print(tmp)