Buggy python submission (verdict: Time Limit Exceeded):
N=int(input())
A=input()
c=0
B1B=0
B1R=0
B1G=0
if A[0]=="B":
 B1B+=1
elif A[0]=="R":
 B1R+=1
else:
 B1G+=1
for i in range(N-2):
 B2=A[i+1]
 for k in range(N-i-2):
  B3=A[i+2+k]
  if (B2=="B" and B3=="R")or (B2=="R" and B3=="B"):
   c+=B1G
   if (i+2+k)<=(i+1)*2:
    if A[(i+1)*2-(i+2+k)]=="G":
     c-=1
  if (B2=="G" and B3=="R")or (B2=="R" and B3=="G"):
   c+=B1B
   if (i+2+k)<=(i+1)*2:
    if A[(i+1)*2-(i+2+k)]=="B":
     c-=1
  if (B2=="B" and B3=="G")or (B2=="G" and B3=="B"):
   c+=B1R
   if (i+2+k)<=(i+1)*2:
    if A[(i+1)*2-(i+2+k)]=="R":
     c-=1
 if B2=="B":
  B1B+=1
 elif B2=="R":
  B1R+=1
 else:
  B1G+=1
print(c)

Fixed submission:
N=int(input())
A=input()
c=0
B1B=0
B1R=0
B1G=0
if A[0]=="B":
 B1B+=1
elif A[0]=="R":
 B1R+=1
else:
 B1G+=1
for i in range(N-2):
 B2=A[i+1]
 for k in range(N-i-2):
  B3=A[i+2+k]
  if (B2=="B" and B3=="R")or (B2=="R" and B3=="B"):
   c+=B1G
   if (i+2+k)<=(i+1)*2:
    if A[(i+1)*2-(i+2+k)]=="G":
     c-=1
  if (B2=="G" and B3=="R")or (B2=="R" and B3=="G"):
   c+=B1B
   if (i+2+k)<=(i+1)*2:
    if A[(i+1)*2-(i+2+k)]=="B":
     c-=1
  if (B2=="B" and B3=="G")or (B2=="G" and B3=="B"):
   c+=B1R
   if (i+2+k)<=(i+1)*2:
    if A[(i+1)*2-(i+2+k)]=="R":
     c-=1
 if B2=="B":
  B1B+=1
 elif B2=="R":
  B1R+=1
 else:
  B1G+=1
print(c)

Buggy python submission (verdict: Time Limit Exceeded):
N=int(input())
A=input()
c=0
for i in range(N-2):
 B2=A[i+1]
 B1B=0
 B1R=0
 B1G=0
 for j in range(i+1):
  if A[j]=="B":
   B1B+=1
  elif A[j]=="R":
   B1R+=1
  else:
   B1G+=1
 for k in range(N-i-2):
  B3=A[i+2+k]
  if (B2=="B" and B3=="R")or (B2=="R" and B3=="B"):
   c+=B1G
   if (i+2+k)<=(i+1)*2:
    if A[(i+1)*2-(i+2+k)]=="G":
     c-=1
  if (B2=="G" and B3=="R")or (B2=="R" and B3=="G"):
   c+=B1B
   if (i+2+k)<=(i+1)*2:
    if A[(i+1)*2-(i+2+k)]=="B":
     c-=1
  if (B2=="B" and B3=="G")or (B2=="G" and B3=="B"):
   c+=B1R
   if (i+2+k)<=(i+1)*2:
    if A[(i+1)*2-(i+2+k)]=="R":
     c-=1
print(c)

Fixed submission:
N=int(input())
A=input()
c=0
B1B=0
B1R=0
B1G=0
if A[0]=="B":
 B1B+=1
elif A[0]=="R":
 B1R+=1
else:
 B1G+=1
for i in range(N-2):
 B2=A[i+1]
 for k in range(N-i-2):
  B3=A[i+2+k]
  if (B2=="B" and B3=="R")or (B2=="R" and B3=="B"):
   c+=B1G
   if (i+2+k)<=(i+1)*2:
    if A[(i+1)*2-(i+2+k)]=="G":
     c-=1
  if (B2=="G" and B3=="R")or (B2=="R" and B3=="G"):
   c+=B1B
   if (i+2+k)<=(i+1)*2:
    if A[(i+1)*2-(i+2+k)]=="B":
     c-=1
  if (B2=="B" and B3=="G")or (B2=="G" and B3=="B"):
   c+=B1R
   if (i+2+k)<=(i+1)*2:
    if A[(i+1)*2-(i+2+k)]=="R":
     c-=1
 if B2=="B":
  B1B+=1
 elif B2=="R":
  B1R+=1
 else:
  B1G+=1
print(c)

Buggy python submission (verdict: Time Limit Exceeded):
N=int(input())
A=input()
c=0
for i in range(N-2):
 B2=A[i+1]
 for j in range(i+1):
  B1=A[j]
  if B1!=B2:
   for k in range(N-i-2):
    B3=A[i+2+k]
    if B2==B3 or B1==B3 or i==j+k:
     continue
    else:
     c+=1
print(c)


Fixed submission:
N=int(input())
A=input()
c=0
B1B=0
B1R=0
B1G=0
if A[0]=="B":
 B1B+=1
elif A[0]=="R":
 B1R+=1
else:
 B1G+=1
for i in range(N-2):
 B2=A[i+1]
 for k in range(N-i-2):
  B3=A[i+2+k]
  if (B2=="B" and B3=="R")or (B2=="R" and B3=="B"):
   c+=B1G
   if (i+2+k)<=(i+1)*2:
    if A[(i+1)*2-(i+2+k)]=="G":
     c-=1
  if (B2=="G" and B3=="R")or (B2=="R" and B3=="G"):
   c+=B1B
   if (i+2+k)<=(i+1)*2:
    if A[(i+1)*2-(i+2+k)]=="B":
     c-=1
  if (B2=="B" and B3=="G")or (B2=="G" and B3=="B"):
   c+=B1R
   if (i+2+k)<=(i+1)*2:
    if A[(i+1)*2-(i+2+k)]=="R":
     c-=1
 if B2=="B":
  B1B+=1
 elif B2=="R":
  B1R+=1
 else:
  B1G+=1
print(c)

Buggy python submission (verdict: Time Limit Exceeded):
N=int(input())
A=input()
c=0
for i in range(N-2):
 B2=A[i+1]
 for j in range(i+1):
  B1=A[j]
  for k in range(N-i-2):
   B3=A[i+2+k]
   if B1==B2 or B2==B3 or B1==B3 or i==j+k:
    continue
   else:
    c+=1
print(c)


Fixed submission:
N=int(input())
A=input()
c=0
B1B=0
B1R=0
B1G=0
if A[0]=="B":
 B1B+=1
elif A[0]=="R":
 B1R+=1
else:
 B1G+=1
for i in range(N-2):
 B2=A[i+1]
 for k in range(N-i-2):
  B3=A[i+2+k]
  if (B2=="B" and B3=="R")or (B2=="R" and B3=="B"):
   c+=B1G
   if (i+2+k)<=(i+1)*2:
    if A[(i+1)*2-(i+2+k)]=="G":
     c-=1
  if (B2=="G" and B3=="R")or (B2=="R" and B3=="G"):
   c+=B1B
   if (i+2+k)<=(i+1)*2:
    if A[(i+1)*2-(i+2+k)]=="B":
     c-=1
  if (B2=="B" and B3=="G")or (B2=="G" and B3=="B"):
   c+=B1R
   if (i+2+k)<=(i+1)*2:
    if A[(i+1)*2-(i+2+k)]=="R":
     c-=1
 if B2=="B":
  B1B+=1
 elif B2=="R":
  B1R+=1
 else:
  B1G+=1
print(c)