Buggy python submission (verdict: Time Limit Exceeded):
n = int(input())
s = input()
r = []
g = []
b = []
for i in range(n):
	if s[i] == "R":
		r.append(i)
	elif s[i] == "G":
		g.append(i)
	else:
		b.append(i)
count = 0
unchi = b
for i in r:
	for j in g:
		u = abs(i-j)
		count += [0,1][(max(i,j)+u) in unchi] + [0,1][(min(i,j)-u) in unchi] + [0,1][u%2 == 0 and (i+j)//2 in unchi]
print(len(r)*len(g)*len(b)-count)

Fixed submission:
from collections import Counter
# これは, u749194f さんの改造です。
# オリジナルではございません。
# https://atcoder.jp/contests/abc162/submissions/11825963
n = int(input())
s = input()
flag = True
if len(set(s))<=2:
    print(0)
    flag = False
if flag:
    r = [i+1 for i in range(n) if s[i]=='R']
    b = [i+1 for i in range(n) if s[i]=='B']
    g = [i+1 for i in range(n) if s[i]=='G']
    minus = 0
    def cnt_cmb(a, b, c):
        cnt = 0
        set_c = set(c)
        for i in a:
            for j in b:
                if (i+j)/2 in set_c:
                    cnt += 1
        return cnt
    minus += cnt_cmb(r, b, g)
    minus += cnt_cmb(b, g, r)
    minus += cnt_cmb(g, r, b)
    a = Counter(s)
    rslt = 1
    for value in a.values():
        rslt *= value
    print(len(r)*len(b)*len(g)-minus)

Buggy python submission (verdict: Time Limit Exceeded):
n = int(input())
s = input()
r = []
g = []
b = []
for i in range(n):
	if s[i] == "R":
		r.append(i)
	elif s[i] == "G":
		g.append(i)
	else:
		b.append(i)
count = 0
unchi = b
for i in r:
	for j in g:
		u = abs(i-j)
		count += [0,1][(max(i,j)+u) in unchi] + [0,1][(min(i,j)-u) in unchi] + [0,1][u%2 == 0 and (i+j)//2 in unchi]
print(len(r)*len(g)*len(b)-count)

Fixed submission:
from collections import Counter
# これは, u749194f さんの改造です。
# オリジナルではございません。
# https://atcoder.jp/contests/abc162/submissions/11825963
n = int(input())
s = input()
flag = True
if len(set(s))<=2:
    print(0)
    flag = False
if flag:
    r = [i+1 for i in range(n) if s[i]=='R']
    b = [i+1 for i in range(n) if s[i]=='B']
    g = [i+1 for i in range(n) if s[i]=='G']
    minus = 0
    def cnt_cmb(a, b, c):
        cnt = 0
        set_c = set(c)
        for i in a:
            for j in b:
                if (i+j)/2 in set_c:
                    cnt += 1
        return cnt
    minus += cnt_cmb(r, b, g)
    minus += cnt_cmb(b, g, r)
    minus += cnt_cmb(g, r, b)
    a = Counter(s)
    rslt = 1
    for value in a.values():
        rslt *= value
    print(len(r)*len(b)*len(g)-minus)

Buggy python submission (verdict: Time Limit Exceeded):
# これは, u749194f さんの改造です。
# オリジナルではございません。
# https://atcoder.jp/contests/abc162/submissions/11825963
n = int(input())
s = input()
flag = True
if len(set(s))<=2:
    print(0)
    flag = False
if flag:
    r = [i+1 for i in range(n) if s[i]=='R']
    b = [i+1 for i in range(n) if s[i]=='B']
    g = [i+1 for i in range(n) if s[i]=='G']
    minus = 0
    def cnt_cmb(a, b, c):
        cnt = 0
        for i in a:
            for j in b:
                if (i+j)/2 in c:
                    cnt += 1
        return cnt
    minus += cnt_cmb(r, b, g)
    minus += cnt_cmb(b, g, r)
    minus += cnt_cmb(g, r, b)
    print(len(r)*len(b)*len(g)-minus)

Fixed submission:
from collections import Counter
# これは, u749194f さんの改造です。
# オリジナルではございません。
# https://atcoder.jp/contests/abc162/submissions/11825963
n = int(input())
s = input()
flag = True
if len(set(s))<=2:
    print(0)
    flag = False
if flag:
    r = [i+1 for i in range(n) if s[i]=='R']
    b = [i+1 for i in range(n) if s[i]=='B']
    g = [i+1 for i in range(n) if s[i]=='G']
    minus = 0
    def cnt_cmb(a, b, c):
        cnt = 0
        set_c = set(c)
        for i in a:
            for j in b:
                if (i+j)/2 in set_c:
                    cnt += 1
        return cnt
    minus += cnt_cmb(r, b, g)
    minus += cnt_cmb(b, g, r)
    minus += cnt_cmb(g, r, b)
    a = Counter(s)
    rslt = 1
    for value in a.values():
        rslt *= value
    print(len(r)*len(b)*len(g)-minus)

Buggy python submission (verdict: Time Limit Exceeded):
n = int(input())
s = input()
r = []
g = []
b = []
for i in range(n):
	if s[i] == "R":
		r.append(i)
	elif s[i] == "G":
		g.append(i)
	else:
		b.append(i)
count = 0
x = []
y = []
z = []
for i in [r,g,b]:
	if len(i) == min([len(r),len(g),len(b)]) and x == []:
		x = i
	elif len(i) == max([len(r),len(g),len(b)]) and z == []:
		z = i
	else:
		y = i
for i in x:
	for j in y:
		u = abs(i-j)
		count += [0,1][(max(i,j)+u) in z] + [0,1][(min(i,j)-u) in z] + [0,1][u%2 == 0 and (i+j)//2 in z]
print(len(r)*len(g)*len(b)-count)

Fixed submission:
from collections import Counter
# これは, u749194f さんの改造です。
# オリジナルではございません。
# https://atcoder.jp/contests/abc162/submissions/11825963
n = int(input())
s = input()
flag = True
if len(set(s))<=2:
    print(0)
    flag = False
if flag:
    r = [i+1 for i in range(n) if s[i]=='R']
    b = [i+1 for i in range(n) if s[i]=='B']
    g = [i+1 for i in range(n) if s[i]=='G']
    minus = 0
    def cnt_cmb(a, b, c):
        cnt = 0
        set_c = set(c)
        for i in a:
            for j in b:
                if (i+j)/2 in set_c:
                    cnt += 1
        return cnt
    minus += cnt_cmb(r, b, g)
    minus += cnt_cmb(b, g, r)
    minus += cnt_cmb(g, r, b)
    a = Counter(s)
    rslt = 1
    for value in a.values():
        rslt *= value
    print(len(r)*len(b)*len(g)-minus)

Buggy python submission (verdict: Time Limit Exceeded):
n = int(input())
s = input()
r = []
g = []
b = []
for i in range(n):
	if s[i] == "R":
		r.append(i)
	elif s[i] == "G":
		g.append(i)
	else:
		b.append(i)
count = 0
x = []
y = []
z = []
for i in [r,g,b]:
	if len(i) == min([len(r),len(g),len(b)]) and x == []:
		x = i
	elif len(i) == max([len(r),len(g),len(b)]) and z == []:
		z = i
	else:
		y = i
for i in x:
	for j in y:
		u = abs(i-j)
		count += [0,1][(max(i,j)+u) in z] + [0,1][(min(i,j)-u) in z] + [0,1][u%2 == 0 and (i+j)//2 in z]
print(len(r)*len(g)*len(b)-count)

Fixed submission:
from collections import Counter
# これは, u749194f さんの改造です。
# オリジナルではございません。
# https://atcoder.jp/contests/abc162/submissions/11825963
n = int(input())
s = input()
flag = True
if len(set(s))<=2:
    print(0)
    flag = False
if flag:
    r = [i+1 for i in range(n) if s[i]=='R']
    b = [i+1 for i in range(n) if s[i]=='B']
    g = [i+1 for i in range(n) if s[i]=='G']
    minus = 0
    def cnt_cmb(a, b, c):
        cnt = 0
        set_c = set(c)
        for i in a:
            for j in b:
                if (i+j)/2 in set_c:
                    cnt += 1
        return cnt
    minus += cnt_cmb(r, b, g)
    minus += cnt_cmb(b, g, r)
    minus += cnt_cmb(g, r, b)
    a = Counter(s)
    rslt = 1
    for value in a.values():
        rslt *= value
    print(len(r)*len(b)*len(g)-minus)

Buggy python submission (verdict: Time Limit Exceeded):
n = int(input())
s = input()
r = []
g = []
b = []
for i in range(n):
	if s[i] == "R":
		r.append(i)
	elif s[i] == "G":
		g.append(i)
	else:
		b.append(i)
count = 0
for i in r:
	for j in g:
		u = abs(i-j)
		count += [0,1][(max(i,j)+u) in b] + [0,1][(min(i,j)-u) in b] + [0,1][u%2 == 0 and (i+j)//2 in b]
print(len(r)*len(g)*len(b)-count)

Fixed submission:
from collections import Counter
# これは, u749194f さんの改造です。
# オリジナルではございません。
# https://atcoder.jp/contests/abc162/submissions/11825963
n = int(input())
s = input()
flag = True
if len(set(s))<=2:
    print(0)
    flag = False
if flag:
    r = [i+1 for i in range(n) if s[i]=='R']
    b = [i+1 for i in range(n) if s[i]=='B']
    g = [i+1 for i in range(n) if s[i]=='G']
    minus = 0
    def cnt_cmb(a, b, c):
        cnt = 0
        set_c = set(c)
        for i in a:
            for j in b:
                if (i+j)/2 in set_c:
                    cnt += 1
        return cnt
    minus += cnt_cmb(r, b, g)
    minus += cnt_cmb(b, g, r)
    minus += cnt_cmb(g, r, b)
    a = Counter(s)
    rslt = 1
    for value in a.values():
        rslt *= value
    print(len(r)*len(b)*len(g)-minus)

Buggy python submission (verdict: Time Limit Exceeded):
n = int(input())
s = input()
r = []
g = []
b = []
for i in range(n):
	if s[i] == "R":
		r.append(i)
	elif s[i] == "G":
		g.append(i)
	else:
		b.append(i)
count = 0
for i in r:
	for j in g:
		u = abs(i-j)
		count += [0,1][(max(i,j)+u) in b] + [0,1][(min(i,j)-u) in b] + [0,1][u%2 == 0 and (i+j)//2 in b]
print(len(r)*len(g)*len(b)-count)

Fixed submission:
from collections import Counter
# これは, u749194f さんの改造です。
# オリジナルではございません。
# https://atcoder.jp/contests/abc162/submissions/11825963
n = int(input())
s = input()
flag = True
if len(set(s))<=2:
    print(0)
    flag = False
if flag:
    r = [i+1 for i in range(n) if s[i]=='R']
    b = [i+1 for i in range(n) if s[i]=='B']
    g = [i+1 for i in range(n) if s[i]=='G']
    minus = 0
    def cnt_cmb(a, b, c):
        cnt = 0
        set_c = set(c)
        for i in a:
            for j in b:
                if (i+j)/2 in set_c:
                    cnt += 1
        return cnt
    minus += cnt_cmb(r, b, g)
    minus += cnt_cmb(b, g, r)
    minus += cnt_cmb(g, r, b)
    a = Counter(s)
    rslt = 1
    for value in a.values():
        rslt *= value
    print(len(r)*len(b)*len(g)-minus)

Buggy python submission (verdict: Time Limit Exceeded):
n = int(input())
s = input()
r = []
g = []
b = []
for i in range(n):
	if s[i] == "R":
		r.append(i)
	elif s[i] == "G":
		g.append(i)
	else:
		b.append(i)
count = 0
for i in r:
	for j in g:
		u = abs(i-j)
		if (max(i,j)+u) in b:
			count += 1
		if (min(i,j)-u) in b:
			count += 1
		if u%2 == 0:
			if (i+j)//2 in b:
				count += 1
print(len(r)*len(g)*len(b)-count)

Fixed submission:
from collections import Counter
# これは, u749194f さんの改造です。
# オリジナルではございません。
# https://atcoder.jp/contests/abc162/submissions/11825963
n = int(input())
s = input()
flag = True
if len(set(s))<=2:
    print(0)
    flag = False
if flag:
    r = [i+1 for i in range(n) if s[i]=='R']
    b = [i+1 for i in range(n) if s[i]=='B']
    g = [i+1 for i in range(n) if s[i]=='G']
    minus = 0
    def cnt_cmb(a, b, c):
        cnt = 0
        set_c = set(c)
        for i in a:
            for j in b:
                if (i+j)/2 in set_c:
                    cnt += 1
        return cnt
    minus += cnt_cmb(r, b, g)
    minus += cnt_cmb(b, g, r)
    minus += cnt_cmb(g, r, b)
    a = Counter(s)
    rslt = 1
    for value in a.values():
        rslt *= value
    print(len(r)*len(b)*len(g)-minus)

Buggy python submission (verdict: Time Limit Exceeded):
n = int(input())
s = input()
r = []
g = []
b = []
for i in range(n):
	if s[i] == "R":
		r.append(i)
	if s[i] == "G":
		g.append(i)
	if s[i] == "B":
		b.append(i)
count = len(r)*len(g)*len(b)
for i in r:
	for j in g:
		u = abs(i-j)
		if (max(i,j)+u) in b:
			count -= 1
		if (min(i,j)-u) in b:
			count -= 1
		if u%2 == 0:
			if (i+j)//2 in b:
				count -= 1
print(count)

Fixed submission:
from collections import Counter
# これは, u749194f さんの改造です。
# オリジナルではございません。
# https://atcoder.jp/contests/abc162/submissions/11825963
n = int(input())
s = input()
flag = True
if len(set(s))<=2:
    print(0)
    flag = False
if flag:
    r = [i+1 for i in range(n) if s[i]=='R']
    b = [i+1 for i in range(n) if s[i]=='B']
    g = [i+1 for i in range(n) if s[i]=='G']
    minus = 0
    def cnt_cmb(a, b, c):
        cnt = 0
        set_c = set(c)
        for i in a:
            for j in b:
                if (i+j)/2 in set_c:
                    cnt += 1
        return cnt
    minus += cnt_cmb(r, b, g)
    minus += cnt_cmb(b, g, r)
    minus += cnt_cmb(g, r, b)
    a = Counter(s)
    rslt = 1
    for value in a.values():
        rslt *= value
    print(len(r)*len(b)*len(g)-minus)

Buggy python submission (verdict: Time Limit Exceeded):
n = int(input())
s = input()
r = []
g = []
b = []
for i in range(n):
	if s[i] == "R":
		r.append(i)
	if s[i] == "G":
		g.append(i)
	if s[i] == "B":
		b.append(i)
count = len(r)*len(g)*len(b)
for i in r:
	for j in g:
		if (max(i,j)+abs(i-j)) in b:
			count -= 1
		if (min(i,j)-abs(i-j)) in b:
			count -= 1
		if abs(i-j)%2 == 0:
			if (i+j)//2 in b:
				count -= 1
print(count)

Fixed submission:
from collections import Counter
# これは, u749194f さんの改造です。
# オリジナルではございません。
# https://atcoder.jp/contests/abc162/submissions/11825963
n = int(input())
s = input()
flag = True
if len(set(s))<=2:
    print(0)
    flag = False
if flag:
    r = [i+1 for i in range(n) if s[i]=='R']
    b = [i+1 for i in range(n) if s[i]=='B']
    g = [i+1 for i in range(n) if s[i]=='G']
    minus = 0
    def cnt_cmb(a, b, c):
        cnt = 0
        set_c = set(c)
        for i in a:
            for j in b:
                if (i+j)/2 in set_c:
                    cnt += 1
        return cnt
    minus += cnt_cmb(r, b, g)
    minus += cnt_cmb(b, g, r)
    minus += cnt_cmb(g, r, b)
    a = Counter(s)
    rslt = 1
    for value in a.values():
        rslt *= value
    print(len(r)*len(b)*len(g)-minus)

Buggy python submission (verdict: Time Limit Exceeded):
n = int(input())
s = input()
r = []
g = []
b = []
for i in range(n):
	if s[i] == "R":
		r.append(i)
	if s[i] == "G":
		g.append(i)
	if s[i] == "B":
		b.append(i)
count = len(r)*len(g)*len(b)
for i in r:
	for j in g:
		if (max(i,j)+abs(i-j)) in b:
			count -= 1
		if (min(i,j)-abs(i-j)) in b:
			count -= 1
		if abs(i-j)%2==0 and abs(i-j)!=0 and ((i+j)//2) in b:
			count -= 1
print(count)

Fixed submission:
from collections import Counter
# これは, u749194f さんの改造です。
# オリジナルではございません。
# https://atcoder.jp/contests/abc162/submissions/11825963
n = int(input())
s = input()
flag = True
if len(set(s))<=2:
    print(0)
    flag = False
if flag:
    r = [i+1 for i in range(n) if s[i]=='R']
    b = [i+1 for i in range(n) if s[i]=='B']
    g = [i+1 for i in range(n) if s[i]=='G']
    minus = 0
    def cnt_cmb(a, b, c):
        cnt = 0
        set_c = set(c)
        for i in a:
            for j in b:
                if (i+j)/2 in set_c:
                    cnt += 1
        return cnt
    minus += cnt_cmb(r, b, g)
    minus += cnt_cmb(b, g, r)
    minus += cnt_cmb(g, r, b)
    a = Counter(s)
    rslt = 1
    for value in a.values():
        rslt *= value
    print(len(r)*len(b)*len(g)-minus)