Buggy python submission (verdict: Time Limit Exceeded):
n = int(input())
s = input()

ans = 0
sn = len(s)

r = []
if s[0] == "R":
    r.append(1)
else:
    r.append(0)
g = []
if s[0] == "G":
    g.append(1)
else:
    g.append(0)
b = []
if s[0] == "B":
    b.append(1)
else:
    b.append(0)

for i in range(1, sn):
    if s[i] == "R":
        r.append(r[-1] + 1)
        g.append(g[- 1])
        b.append(b[- 1])
    elif s[i] == "G":
        r.append(r[-1])
        g.append(g[-1] + 1)
        b.append(b[- 1])
    elif s[i] == "B":
        r.append(r[-1])
        g.append(g[-1])
        b.append(b[-1] + 1)
    else:
        r.append(r[-1])
        g.append(g[- 1])
        b.append(b[- 1])

for i in range(n - 2):
    for j in range(i + 1, n - 1):
        if s[i] != s[j]:
            tmp = dict()
            tmp[s[i]] = 0
            tmp[s[j]] = 0
            target_idx = j + (j - i)

            if tmp.get("B", 1) == 1:
                ans += b[-1] - b[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "B":
                    ans -= 1
            elif tmp.get("G", 1) == 1:
                ans += g[-1] - g[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "G":
                    ans -= 1
            else:
                ans += r[-1] - r[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "R":
                    ans -= 1

print(ans)


Fixed submission:
n = int(input())
s = input()

ans = 0
sn = len(s)

r = []
if s[0] == "R":
    r.append(1)
else:
    r.append(0)
g = []
if s[0] == "G":
    g.append(1)
else:
    g.append(0)
b = []
if s[0] == "B":
    b.append(1)
else:
    b.append(0)

for i in range(1, sn):
    if s[i] == "R":
        r.append(r[-1] + 1)
        g.append(g[- 1])
        b.append(b[- 1])
    elif s[i] == "G":
        r.append(r[-1])
        g.append(g[-1] + 1)
        b.append(b[- 1])
    elif s[i] == "B":
        r.append(r[-1])
        g.append(g[-1])
        b.append(b[-1] + 1)
    else:
        r.append(r[-1])
        g.append(g[- 1])
        b.append(b[- 1])

for i in range(n - 2):
    for j in range(i + 1, n - 1):
        if s[i] != s[j]:
            tmp = dict()
            tmp[s[i]] = 0
            tmp[s[j]] = 0
            target_idx = j + (j - i)

            if tmp.get("B", 1) == 1:
                ans += b[-1] - b[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "B":
                    ans -= 1
            elif tmp.get("G", 1) == 1:
                ans += g[-1] - g[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "G":
                    ans -= 1
            else:
                ans += r[-1] - r[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "R":
                    ans -= 1

print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
n = int(input())
s = input()

ans = 0
sn = len(s)

r = []
if s[0] == "R":
    r.append(1)
else:
    r.append(0)

for i in range(1, sn):
    if s[i] == "R":
        r.append(r[-1] + 1)
    else:
        r.append(r[-1])

g = []
if s[0] == "G":
    g.append(1)
else:
    g.append(0)

for i in range(1, sn):
    if s[i] == "G":
        g.append(g[-1] + 1)
    else:
        g.append(g[-1])

b = []
if s[0] == "B":
    b.append(1)
else:
    b.append(0)

for i in range(1, sn):
    if s[i] == "B":
        b.append(b[-1] + 1)
    else:
        b.append(b[-1])


for i in range(n - 2):
    for j in range(i + 1, n - 1):
        if s[i] != s[j]:
            tmp = dict()
            tmp[s[i]] = 0
            tmp[s[j]] = 0
            target_idx = j + (j - i)

            if tmp.get("B", 1) == 1:
                ans += b[-1] - b[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "B":
                    ans -= 1
            elif tmp.get("G", 1) == 1:
                ans += g[-1] - g[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "G":
                    ans -= 1
            else:
                ans += r[-1] - r[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "R":
                    ans -= 1

print(ans)


Fixed submission:
n = int(input())
s = input()

ans = 0
sn = len(s)

r = []
if s[0] == "R":
    r.append(1)
else:
    r.append(0)
g = []
if s[0] == "G":
    g.append(1)
else:
    g.append(0)
b = []
if s[0] == "B":
    b.append(1)
else:
    b.append(0)

for i in range(1, sn):
    if s[i] == "R":
        r.append(r[-1] + 1)
        g.append(g[- 1])
        b.append(b[- 1])
    elif s[i] == "G":
        r.append(r[-1])
        g.append(g[-1] + 1)
        b.append(b[- 1])
    elif s[i] == "B":
        r.append(r[-1])
        g.append(g[-1])
        b.append(b[-1] + 1)
    else:
        r.append(r[-1])
        g.append(g[- 1])
        b.append(b[- 1])

for i in range(n - 2):
    for j in range(i + 1, n - 1):
        if s[i] != s[j]:
            tmp = dict()
            tmp[s[i]] = 0
            tmp[s[j]] = 0
            target_idx = j + (j - i)

            if tmp.get("B", 1) == 1:
                ans += b[-1] - b[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "B":
                    ans -= 1
            elif tmp.get("G", 1) == 1:
                ans += g[-1] - g[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "G":
                    ans -= 1
            else:
                ans += r[-1] - r[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "R":
                    ans -= 1

print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
n = int(input())
s = input()

ans = 0
sn = len(s)

r = []
if s[0] == "R":
    r.append(1)
else:
    r.append(0)

for i in range(1, sn):
    if s[i] == "R":
        r.append(r[-1] + 1)
    else:
        r.append(r[-1])

g = []
if s[0] == "G":
    g.append(1)
else:
    g.append(0)

for i in range(1, sn):
    if s[i] == "G":
        g.append(g[-1] + 1)
    else:
        g.append(g[-1])

b = []
if s[0] == "B":
    b.append(1)
else:
    b.append(0)

for i in range(1, sn):
    if s[i] == "B":
        b.append(b[-1] + 1)
    else:
        b.append(b[-1])

for i in range(n - 2):
    for j in range(i + 1, n - 1):
        if s[i] != s[j]:
            target_idx = j + (j - i)

            if "B" != s[i] and "B" != s[j]:
                ans += b[-1] - b[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "B":
                    ans -= 1
            elif "G" != s[i] and "G" != s[j]:
                ans += g[-1] - g[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "G":
                    ans -= 1
            else:
                ans += r[-1] - r[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "R":
                    ans -= 1

print(ans)


Fixed submission:
n = int(input())
s = input()

ans = 0
sn = len(s)

r = []
if s[0] == "R":
    r.append(1)
else:
    r.append(0)
g = []
if s[0] == "G":
    g.append(1)
else:
    g.append(0)
b = []
if s[0] == "B":
    b.append(1)
else:
    b.append(0)

for i in range(1, sn):
    if s[i] == "R":
        r.append(r[-1] + 1)
        g.append(g[- 1])
        b.append(b[- 1])
    elif s[i] == "G":
        r.append(r[-1])
        g.append(g[-1] + 1)
        b.append(b[- 1])
    elif s[i] == "B":
        r.append(r[-1])
        g.append(g[-1])
        b.append(b[-1] + 1)
    else:
        r.append(r[-1])
        g.append(g[- 1])
        b.append(b[- 1])

for i in range(n - 2):
    for j in range(i + 1, n - 1):
        if s[i] != s[j]:
            tmp = dict()
            tmp[s[i]] = 0
            tmp[s[j]] = 0
            target_idx = j + (j - i)

            if tmp.get("B", 1) == 1:
                ans += b[-1] - b[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "B":
                    ans -= 1
            elif tmp.get("G", 1) == 1:
                ans += g[-1] - g[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "G":
                    ans -= 1
            else:
                ans += r[-1] - r[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "R":
                    ans -= 1

print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
n = int(input())
s = input()

ans = 0

r = []
if s[0] == "R":
    r.append(1)
else:
    r.append(0)

for i in range(1, len(s)):
    if s[i] == "R":
        r.append(r[-1] + 1)
    else:
        r.append(r[-1])

g = []
if s[0] == "G":
    g.append(1)
else:
    g.append(0)

for i in range(1, len(s)):
    if s[i] == "G":
        g.append(g[-1] + 1)
    else:
        g.append(g[-1])

b = []
if s[0] == "B":
    b.append(1)
else:
    b.append(0)

for i in range(1, len(s)):
    if s[i] == "B":
        b.append(b[-1] + 1)
    else:
        b.append(b[-1])

for i in range(n - 2):
    for j in range(i + 1, n - 1):
        if s[i] != s[j]:
            target_idx = j + (j - i)

            if "R" != s[i] and "R" != s[j]:
                ans += r[-1] - r[j]
                if target_idx >= len(s):
                    continue
                if s[target_idx] == "R":
                    ans -= 1
            elif "G" != s[i] and "G" != s[j]:
                ans += g[-1] - g[j]
                if target_idx >= len(s):
                    continue
                if s[target_idx] == "G":
                    ans -= 1
            else:
                ans += b[-1] - b[j]
                if target_idx >= len(s):
                    continue
                if s[target_idx] == "B":
                    ans -= 1

print(ans)


Fixed submission:
n = int(input())
s = input()

ans = 0
sn = len(s)

r = []
if s[0] == "R":
    r.append(1)
else:
    r.append(0)
g = []
if s[0] == "G":
    g.append(1)
else:
    g.append(0)
b = []
if s[0] == "B":
    b.append(1)
else:
    b.append(0)

for i in range(1, sn):
    if s[i] == "R":
        r.append(r[-1] + 1)
        g.append(g[- 1])
        b.append(b[- 1])
    elif s[i] == "G":
        r.append(r[-1])
        g.append(g[-1] + 1)
        b.append(b[- 1])
    elif s[i] == "B":
        r.append(r[-1])
        g.append(g[-1])
        b.append(b[-1] + 1)
    else:
        r.append(r[-1])
        g.append(g[- 1])
        b.append(b[- 1])

for i in range(n - 2):
    for j in range(i + 1, n - 1):
        if s[i] != s[j]:
            tmp = dict()
            tmp[s[i]] = 0
            tmp[s[j]] = 0
            target_idx = j + (j - i)

            if tmp.get("B", 1) == 1:
                ans += b[-1] - b[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "B":
                    ans -= 1
            elif tmp.get("G", 1) == 1:
                ans += g[-1] - g[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "G":
                    ans -= 1
            else:
                ans += r[-1] - r[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "R":
                    ans -= 1

print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
n = int(input())
s = input()

ans = 0

r = []
if s[0] == "R":
    r.append(1)
else:
    r.append(0)

for i in range(1, len(s)):
    if s[i] == "R":
        r.append(r[-1] + 1)
    else:
        r.append(r[-1])

g = []
if s[0] == "G":
    g.append(1)
else:
    g.append(0)

for i in range(1, len(s)):
    if s[i] == "G":
        g.append(g[-1] + 1)
    else:
        g.append(g[-1])

b = []
if s[0] == "B":
    b.append(1)
else:
    b.append(0)

for i in range(1, len(s)):
    if s[i] == "B":
        b.append(b[-1] + 1)
    else:
        b.append(b[-1])

for i in range(n - 2):
    for j in range(i + 1, n):
        if s[i] != s[j]:
            tmp = [s[i]] + [s[j]]
            target_idx = j + (j - i)

            if "R" not in tmp:
                ans += r[-1] - r[j]
                if target_idx >= len(s):
                    continue
                if s[target_idx] == "R":
                    ans -= 1
            elif "G" not in tmp:
                ans += g[-1] - g[j]
                if target_idx >= len(s):
                    continue
                if s[target_idx] == "G":
                    ans -= 1
            else:
                ans += b[-1] - b[j]
                if target_idx >= len(s):
                    continue
                if s[target_idx] == "B":
                    ans -= 1

print(ans)


Fixed submission:
n = int(input())
s = input()

ans = 0
sn = len(s)

r = []
if s[0] == "R":
    r.append(1)
else:
    r.append(0)
g = []
if s[0] == "G":
    g.append(1)
else:
    g.append(0)
b = []
if s[0] == "B":
    b.append(1)
else:
    b.append(0)

for i in range(1, sn):
    if s[i] == "R":
        r.append(r[-1] + 1)
        g.append(g[- 1])
        b.append(b[- 1])
    elif s[i] == "G":
        r.append(r[-1])
        g.append(g[-1] + 1)
        b.append(b[- 1])
    elif s[i] == "B":
        r.append(r[-1])
        g.append(g[-1])
        b.append(b[-1] + 1)
    else:
        r.append(r[-1])
        g.append(g[- 1])
        b.append(b[- 1])

for i in range(n - 2):
    for j in range(i + 1, n - 1):
        if s[i] != s[j]:
            tmp = dict()
            tmp[s[i]] = 0
            tmp[s[j]] = 0
            target_idx = j + (j - i)

            if tmp.get("B", 1) == 1:
                ans += b[-1] - b[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "B":
                    ans -= 1
            elif tmp.get("G", 1) == 1:
                ans += g[-1] - g[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "G":
                    ans -= 1
            else:
                ans += r[-1] - r[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "R":
                    ans -= 1

print(ans)

Buggy python submission (verdict: Time Limit Exceeded):

n = int(input())
s = input()

ans = 0

r = []
if s[0] == "R":
    r.append(1)
else:
    r.append(0)

for i in range(1, len(s)):
    if s[i] == "R":
        r.append(r[-1] + 1)
    else:
        r.append(r[-1])

g = []
if s[0] == "G":
    g.append(1)
else:
    g.append(0)

for i in range(1, len(s)):
    if s[i] == "G":
        g.append(g[-1] + 1)
    else:
        g.append(g[-1])

b = []
if s[0] == "B":
    b.append(1)
else:
    b.append(0)

for i in range(1, len(s)):
    if s[i] == "B":
        b.append(b[-1] + 1)
    else:
        b.append(b[-1])

for i in range(n):
    for j in range(i+1, n):
        if s[i] != s[j]:
            tmp = [s[i]] + [s[j]]
            target_idx = j + (j - i)

            if "R" not in tmp:
                ans += r[-1] - r[j]
                if target_idx >= len(s):
                    continue
                if s[target_idx] == "R":
                    ans -= 1
            elif "G" not in tmp:
                ans += g[-1] - g[j]
                if target_idx >= len(s):
                    continue
                if s[target_idx] == "G":
                    ans -= 1
            else:
                ans += b[-1] - b[j]
                if target_idx >= len(s):
                    continue
                if s[target_idx] == "B":
                    ans -= 1

print(ans)


Fixed submission:
n = int(input())
s = input()

ans = 0
sn = len(s)

r = []
if s[0] == "R":
    r.append(1)
else:
    r.append(0)
g = []
if s[0] == "G":
    g.append(1)
else:
    g.append(0)
b = []
if s[0] == "B":
    b.append(1)
else:
    b.append(0)

for i in range(1, sn):
    if s[i] == "R":
        r.append(r[-1] + 1)
        g.append(g[- 1])
        b.append(b[- 1])
    elif s[i] == "G":
        r.append(r[-1])
        g.append(g[-1] + 1)
        b.append(b[- 1])
    elif s[i] == "B":
        r.append(r[-1])
        g.append(g[-1])
        b.append(b[-1] + 1)
    else:
        r.append(r[-1])
        g.append(g[- 1])
        b.append(b[- 1])

for i in range(n - 2):
    for j in range(i + 1, n - 1):
        if s[i] != s[j]:
            tmp = dict()
            tmp[s[i]] = 0
            tmp[s[j]] = 0
            target_idx = j + (j - i)

            if tmp.get("B", 1) == 1:
                ans += b[-1] - b[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "B":
                    ans -= 1
            elif tmp.get("G", 1) == 1:
                ans += g[-1] - g[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "G":
                    ans -= 1
            else:
                ans += r[-1] - r[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "R":
                    ans -= 1

print(ans)

Buggy python submission (verdict: Time Limit Exceeded):

n = int(input())
s = input()

ans = 0

r = []
if s[0] == "R":
    r.append(1)
else:
    r.append(0)

for i in range(1, len(s)):
    if s[i] == "R":
        r.append(r[-1] + 1)
    else:
        r.append(r[-1])

g = []
if s[0] == "G":
    g.append(1)
else:
    g.append(0)

for i in range(1, len(s)):
    if s[i] == "G":
        g.append(g[-1] + 1)
    else:
        g.append(g[-1])

b = []
if s[0] == "B":
    b.append(1)
else:
    b.append(0)

for i in range(1, len(s)):
    if s[i] == "B":
        b.append(b[-1] + 1)
    else:
        b.append(b[-1])

for i in range(n):
    for j in range(i+1, n):
        if s[i] == s[j]:
            continue
        else:
            tmp = [s[i]] + [s[j]]
            target_idx = j + (j - i)

            if "R" not in tmp:
                ans += r[-1] - r[j]
                if target_idx >= len(s):
                    continue
                if s[target_idx] == "R":
                    ans -= 1
            elif "G" not in tmp:
                ans += g[-1] - g[j]
                if target_idx >= len(s):
                    continue
                if s[target_idx] == "G":
                    ans -= 1
            else:
                ans += b[-1] - b[j]
                if target_idx >= len(s):
                    continue
                if s[target_idx] == "B":
                    ans -= 1

print(ans)


Fixed submission:
n = int(input())
s = input()

ans = 0
sn = len(s)

r = []
if s[0] == "R":
    r.append(1)
else:
    r.append(0)
g = []
if s[0] == "G":
    g.append(1)
else:
    g.append(0)
b = []
if s[0] == "B":
    b.append(1)
else:
    b.append(0)

for i in range(1, sn):
    if s[i] == "R":
        r.append(r[-1] + 1)
        g.append(g[- 1])
        b.append(b[- 1])
    elif s[i] == "G":
        r.append(r[-1])
        g.append(g[-1] + 1)
        b.append(b[- 1])
    elif s[i] == "B":
        r.append(r[-1])
        g.append(g[-1])
        b.append(b[-1] + 1)
    else:
        r.append(r[-1])
        g.append(g[- 1])
        b.append(b[- 1])

for i in range(n - 2):
    for j in range(i + 1, n - 1):
        if s[i] != s[j]:
            tmp = dict()
            tmp[s[i]] = 0
            tmp[s[j]] = 0
            target_idx = j + (j - i)

            if tmp.get("B", 1) == 1:
                ans += b[-1] - b[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "B":
                    ans -= 1
            elif tmp.get("G", 1) == 1:
                ans += g[-1] - g[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "G":
                    ans -= 1
            else:
                ans += r[-1] - r[j]
                if target_idx >= sn:
                    continue
                if s[target_idx] == "R":
                    ans -= 1

print(ans)