Buggy python submission (verdict: Time Limit Exceeded):
import sys

stdin = sys.stdin
 
ri = lambda: int(rs())
rl = lambda: list(map(int, stdin.readline().split()))
rs = lambda: stdin.readline().rstrip()  # ignore trailing spaces

#実際に書き込む
N = ri()
S = [rs() for _ in range(N)]
answer = 0
a = 0
for b in range(N):
    bool = True
    for i in range(N):
        for j in range(i+1, N):
            y1 = i
            x1 = (j+b)%(N)
            y2 = j
            x2 = (i+b)%(N)
            if S[y1][x1] != S[y2][x2]:
                bool = False
                break
        else:
            continue
        break
    else:
        if bool:
            #print(a, b, i, j, y1, x1, y2, x2)
            answer += 1
answer *= N
print(answer)

#16



Fixed submission:
import sys
import numpy as np

stdin = sys.stdin
 
ri = lambda: int(rs())
rl = lambda: list(map(int, stdin.readline().split()))
rs = lambda: stdin.readline().rstrip() # ignore trailing spaces

N = ri()
S = np.array([list(rs()) for _ in range(N)])

S = np.concatenate([S, S], axis=0)
answer = 0
for b in range(N):
    S2 = S[b:b+N]
    if (S2 == S2.T).all():
        answer += N

print(answer)

Buggy python submission (verdict: Time Limit Exceeded):
import sys

stdin = sys.stdin
 
ri = lambda: int(rs())
rl = lambda: list(map(int, stdin.readline().split()))
rs = lambda: stdin.readline().rstrip()  # ignore trailing spaces

#実際に書き込む
N = ri()
S = [rs() for _ in range(N)]
answer = 0
a = 0
for b in range(N):
    bool = True
    for i in range(N):
        for j in range(i+1, N):
            y1 = (i+a)%(N)
            x1 = (j+b)%(N)
            y2 = (j+a)%(N)
            x2 = (i+b)%(N)
            
            if S[y1][x1] != S[y2][x2]:
                
                bool = False
                break
        else:
            continue
        break
    else:
        if bool:
            #print(a, b, i, j, y1, x1, y2, x2)
            answer += 1
answer *= N
print(answer)

#16



Fixed submission:
import sys
import numpy as np

stdin = sys.stdin
 
ri = lambda: int(rs())
rl = lambda: list(map(int, stdin.readline().split()))
rs = lambda: stdin.readline().rstrip() # ignore trailing spaces

N = ri()
S = np.array([list(rs()) for _ in range(N)])

S = np.concatenate([S, S], axis=0)
answer = 0
for b in range(N):
    S2 = S[b:b+N]
    if (S2 == S2.T).all():
        answer += N

print(answer)

Buggy python submission (verdict: Time Limit Exceeded):
import sys

stdin = sys.stdin
 
ri = lambda: int(rs())
rl = lambda: list(map(int, stdin.readline().split()))
rs = lambda: stdin.readline().rstrip()  # ignore trailing spaces

#実際に書き込む
N = ri()
S = [rs() for _ in range(N)]
answer = 0
for a in range(N):
    for b in range(N):
        bool = True
        for i in range(N):
            for j in range(i+1, N):
                y1 = (i+a)%(N)
                x1 = (j+b)%(N)
                y2 = (j+a)%(N)
                x2 = (i+b)%(N)
                
                if S[y1][x1] != S[y2][x2]:
                    
                    bool = False
                    break
            else:
                continue
            break
        else:
            if bool:
                #print(a, b, i, j, y1, x1, y2, x2)
                answer += 1
print(answer)

#16



Fixed submission:
import sys
import numpy as np

stdin = sys.stdin
 
ri = lambda: int(rs())
rl = lambda: list(map(int, stdin.readline().split()))
rs = lambda: stdin.readline().rstrip() # ignore trailing spaces

N = ri()
S = np.array([list(rs()) for _ in range(N)])

S = np.concatenate([S, S], axis=0)
answer = 0
for b in range(N):
    S2 = S[b:b+N]
    if (S2 == S2.T).all():
        answer += N

print(answer)