Problem:
Snuke, who loves animals, built a zoo.  There are N animals in this zoo. They are conveniently numbered 1 through N, and arranged in a circle. The animal numbered i (2≤i≤N-1) is adjacent to the animals numbered i-1 and i+1. Also, the animal numbered 1 is adjacent to the animals numbered 2 and N, and the animal numbered N is adjacent to the animals numbered N-1 and 1.  There are two kinds of animals in this zoo: honest sheep that only speak the truth, and lying wolves that only tell lies.  Snuke cannot tell the difference between these two species, and asked each animal the following question: "Are your neighbors of the same species?" The animal numbered i answered s_i. Here, if s_i is `o`, the animal said that the two neighboring animals are of the same species, and if s_i is `x`, the animal said that the two neighboring animals are of different species.  More formally, a sheep answered `o` if the two neighboring animals are both sheep or both wolves, and answered `x` otherwise. Similarly, a wolf answered `x` if the two neighboring animals are both sheep or both wolves, and answered `o` otherwise.  Snuke is wondering whether there is a valid assignment of species to the animals that is consistent with these responses. If there is such an assignment, show one such assignment. Otherwise, print `-1`.

Incorrect submission (verdict: Wrong Answer):
n=int(input())
s = list(input())
l = list(0 for i in range(n))
l[0]='S'
l[1]='S'
for i in range(1,n-1):
    if l[i]=='S':
        if l[i-1]=='S':
            if (s[i]=='○'):
                s[i+1]='S'
            else:
                s[i+1]='W'
        else:
            if s[i]=='○':
                s[i+1]='W'
            else:
                s[i+1]='S'
    else:
        if l[i-1]=='S':
            if (s[i]=='○'):
                s[i+1]='W'
            else:
                s[i+1]='S'
        else:
            if s[i]=='○':
                s[i+1]='S'
            else:
                s[i+1]='W'
if l[n-1]=='S':
    if l[n-2]=='S':
        if (s[n-1]=='○'):
            if s[0]=='S':
                print(l)
                exit
        else:
            if s[0]=='W':
                print(l)                   
                exit
    else:
        if s[n-1]=='○':
            if s[0]=='W':
                print(l)
                exit
        else:
            if s[0]=='S':
                print(l)
                exit
else:
    if l[n-2]=='S':
        if (s[n-1]=='○'):
            if s[0]=='W':
                print(l)
                exit
        else:
            if s[0]=='S':
                print(l)
                exit
    else:
        if s[n-1]=='○':
            if s[0]=='S':
                print(l)
                exit
        else:
            if s[0]=='W':
                print(l)                    
                exit
l[0]='S'
l[1]='W'
for i in range(1,n-1):
    if l[i]=='S':
        if l[i-1]=='S':
            if (s[i]=='○'):
                s[i+1]='S'
            else:
                s[i+1]='W'
        else:
            if s[i]=='○':
                s[i+1]='W'
            else:
                s[i+1]='S'
    else:
        if l[i-1]=='S':
            if (s[i]=='○'):
                s[i+1]='W'
            else:
                s[i+1]='S'
        else:
            if s[i]=='○':
                s[i+1]='S'
            else:
                s[i+1]='W'
if l[n-1]=='S':
    if l[n-2]=='S':
        if (s[n-1]=='○'):
            if s[0]=='S':
                print(l)
                exit
        else:
            if s[0]=='W':
                print(l)                   
                exit
    else:
        if s[n-1]=='○':
            if s[0]=='W':
                print(l)
                exit
        else:
            if s[0]=='S':
                print(l)
                exit
else:
    if l[n-2]=='S':
        if (s[n-1]=='○'):
            if s[0]=='W':
                print(l)
                exit
        else:
            if s[0]=='S':
                print(l)
                exit
    else:
        if s[n-1]=='○':
            if s[0]=='S':
                print(l)
                exit
        else:
            if s[0]=='W':
                print(l)                    
                exit
l[0]='W'
l[1]='S'
for i in range(1,n-1):
    if l[i]=='S':
        if l[i-1]=='S':
            if (s[i]=='○'):
                s[i+1]='S'
            else:
                s[i+1]='W'
        else:
            if s[i]=='○':
                s[i+1]='W'
            else:
                s[i+1]='S'
    else:
        if l[i-1]=='S':
            if (s[i]=='○'):
                s[i+1]='W'
            else:
                s[i+1]='S'
        else:
            if s[i]=='○':
                s[i+1]='S'
            else:
                s[i+1]='W'
if l[n-1]=='S':
    if l[n-2]=='S':
        if (s[n-1]=='○'):
            if s[0]=='S':
                print(l)
                exit
        else:
            if s[0]=='W':
                print(l)                   
                exit
    else:
        if s[n-1]=='○':
            if s[0]=='W':
                print(l)
                exit
        else:
            if s[0]=='S':
                print(l)
                exit
else:
    if l[n-2]=='S':
        if (s[n-1]=='○'):
            if s[0]=='W':
                print(l)
                exit
        else:
            if s[0]=='S':
                print(l)
                exit
    else:
        if s[n-1]=='○':
            if s[0]=='S':
                print(l)
                exit
        else:
            if s[0]=='W':
                print(l)                    
                exit
l[0]='W'
l[1]='W'
for i in range(1,n-1):
    if l[i]=='S':
        if l[i-1]=='S':
            if (s[i]=='○'):
                s[i+1]='S'
            else:
                s[i+1]='W'
        else:
            if s[i]=='○':
                s[i+1]='W'
            else:
                s[i+1]='S'
    else:
        if l[i-1]=='S':
            if (s[i]=='○'):
                s[i+1]='W'
            else:
                s[i+1]='S'
        else:
            if s[i]=='○':
                s[i+1]='S'
            else:
                s[i+1]='W'
if l[n-1]=='S':
    if l[n-2]=='S':
        if (s[n-1]=='○'):
            if s[0]=='S':
                print(l)
                exit
        else:
            if s[0]=='W':
                print(l)                   
                exit
    else:
        if s[n-1]=='○':
            if s[0]=='W':
                print(l)
                exit
        else:
            if s[0]=='S':
                print(l)
                exit
else:
    if l[n-2]=='S':
        if (s[n-1]=='○'):
            if s[0]=='W':
                print(l)
                exit
        else:
            if s[0]=='S':
                print(l)
                exit
    else:
        if s[n-1]=='○':
            if s[0]=='S':
                print(l)
                exit
        else:
            if s[0]=='W':
                print(l)                    
                exit
    

        



Fixed, accepted submission:
import sys
n=int(input())
s = list(input())
l = list(0 for i in range(n))
l[0]='S'
l[1]='S'
for i in range(1,n-1):
    if l[i]=='S':
        if l[i-1]=='S':
            if (s[i]=='o'):
                l[i+1]='S'
            else:
                l[i+1]='W'
        else:
            if s[i]=='o':
                l[i+1]='W'
            else:
                l[i+1]='S'
    else:
        if l[i-1]=='S':
            if (s[i]=='o'):
                l[i+1]='W'
            else:
                l[i+1]='S'
        else:
            if s[i]=='o':
                l[i+1]='S'
            else:
                l[i+1]='W'
if l[n-1]=='S':
    if l[n-2]=='S':
        if (s[n-1]=='o'):
            if l[0]=='S':
                if s[0]=='o':
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()  
        else:
            if l[0]=='W':
                if s[0]=='o':
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()    
    else:
        if s[n-1]=='o':
            if l[0]=='W':
                if s[0]=='o':
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()    
        else:
            if l[0]=='S':
                if s[0]=='o':
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()    
else:
    if l[n-2]=='S':
        if (s[n-1]=='o'):
            if l[0]=='W':
                if s[0]=='o':
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()    
        else:
            if l[0]=='S':
                if s[0]=='o':
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()   
    else:
        if s[n-1]=='o':
            if l[0]=='S':
                if s[0]=='o':
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()  
        else:
            if l[0]=='W':
                if s[0]=='o':
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()   
l[0]='S'
l[1]='W'
for i in range(1,n-1):
    if l[i]=='S':
        if l[i-1]=='S':
            if (s[i]=='o'):
                l[i+1]='S'
            else:
                l[i+1]='W'
        else:
            if s[i]=='o':
                l[i+1]='W'
            else:
                l[i+1]='S'
    else:
        if l[i-1]=='S':
            if (s[i]=='o'):
                l[i+1]='W'
            else:
                l[i+1]='S'
        else:
            if s[i]=='o':
                l[i+1]='S'
            else:
                l[i+1]='W'
if l[n-1]=='S':
    if l[n-2]=='S':
        if (s[n-1]=='o'):
            if l[0]=='S':
                if s[0]=='o':
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()  
        else:
            if l[0]=='W':
                if s[0]=='o':
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()    
    else:
        if s[n-1]=='o':
            if l[0]=='W':
                if s[0]=='o':
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()    
        else:
            if l[0]=='S':
                if s[0]=='o':
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()    
else:
    if l[n-2]=='S':
        if (s[n-1]=='o'):
            if l[0]=='W':
                if s[0]=='o':
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()    
        else:
            if l[0]=='S':
                if s[0]=='o':
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()   
    else:
        if s[n-1]=='o':
            if l[0]=='S':
                if s[0]=='o':
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()  
        else:
            if l[0]=='W':
                if s[0]=='o':
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()   
l[0]='W'
l[1]='S'
for i in range(1,n-1):
    if l[i]=='S':
        if l[i-1]=='S':
            if (s[i]=='o'):
                l[i+1]='S'
            else:
                l[i+1]='W'
        else:
            if s[i]=='o':
                l[i+1]='W'
            else:
                l[i+1]='S'
    else:
        if l[i-1]=='S':
            if (s[i]=='o'):
                l[i+1]='W'
            else:
                l[i+1]='S'
        else:
            if s[i]=='o':
                l[i+1]='S'
            else:
                l[i+1]='W'
if l[n-1]=='S':
    if l[n-2]=='S':
        if (s[n-1]=='o'):
            if l[0]=='S':
                if s[0]=='o':
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()  
        else:
            if l[0]=='W':
                if s[0]=='o':
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()    
    else:
        if s[n-1]=='o':
            if l[0]=='W':
                if s[0]=='o':
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()    
        else:
            if l[0]=='S':
                if s[0]=='o':
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()    
else:
    if l[n-2]=='S':
        if (s[n-1]=='o'):
            if l[0]=='W':
                if s[0]=='o':
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()    
        else:
            if l[0]=='S':
                if s[0]=='o':
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()   
    else:
        if s[n-1]=='o':
            if l[0]=='S':
                if s[0]=='o':
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()  
        else:
            if l[0]=='W':
                if s[0]=='o':
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()   
l[0]='W'
l[1]='W'
for i in range(1,n-1):
    if l[i]=='S':
        if l[i-1]=='S':
            if (s[i]=='o'):
                l[i+1]='S'
            else:
                l[i+1]='W'
        else:
            if s[i]=='o':
                l[i+1]='W'
            else:
                l[i+1]='S'
    else:
        if l[i-1]=='S':
            if (s[i]=='o'):
                l[i+1]='W'
            else:
                l[i+1]='S'
        else:
            if s[i]=='o':
                l[i+1]='S'
            else:
                l[i+1]='W'
if l[n-1]=='S':
    if l[n-2]=='S':
        if (s[n-1]=='o'):
            if l[0]=='S':
                if s[0]=='o':
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()    
        else:
            if l[0]=='W':
                if s[0]=='o':
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()    
    else:
        if s[n-1]=='o':
            if l[0]=='W':
                if s[0]=='o':
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()    
        else:
            if l[0]=='S':
                if s[0]=='o':
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()    
else:
    if l[n-2]=='S':
        if (s[n-1]=='o'):
            if l[0]=='W':
                if s[0]=='o':
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()    
        else:
            if l[0]=='S':
                if s[0]=='o':
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()    
    else:
        if s[n-1]=='o':
            if l[0]=='S':
                if s[0]=='o':
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()    
        else:
            if l[0]=='W':
                if s[0]=='o':
                    if l[n-1]!=l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()
                else:
                    if l[n-1]==l[1]:
                        l=''.join(l)
                        print(l)
                        sys.exit()    
print(-1)