Buggy python submission (verdict: Runtime Error):
import sys


def input(): return sys.stdin.readline().strip()
def I(): return int(input())
def LI(): return list(map(int, input().split()))
def IR(n): return [I() for i in range(n)]
def LIR(n): return [LI() for i in range(n)]
def SR(n): return [S() for i in range(n)]
def S(): return input()
def LS(): return input().split()


INF = float('inf')


def calc_rle_l(s):
    now_c = s[0]
    count = 1
    res = []
    for i in range(1, len(s)):
        if now_c == s[i]:  # 同じ文字が続く
            count += 1
        else:  # 手前まで続いた文字を集計
            res.append([now_c, count])
            now_c = s[i]
            count = 1
    res.append([now_c, count])  # 最後に続く文字
    return res


s = S()
if len(set(s)) < 2:  # B か W しかない
    print(0)
    sys.exit()

rle = calc_rle_l(s)
# print(rle)
if rle[0][1] == 'W':
    rle = rle[1:]
if rle[-1][1] == 'B':
    rle = rle[:-1]
ans = 0
for i in range(0, len(rle), 2):
    ans += rle[i][1] * rle[i + 1][1]
    if i + 2 < len(rle):
        rle[i + 2][1] += rle[i][1]
print(ans)


Fixed submission:
import sys


def input(): return sys.stdin.readline().strip()
def I(): return int(input())
def LI(): return list(map(int, input().split()))
def IR(n): return [I() for i in range(n)]
def LIR(n): return [LI() for i in range(n)]
def SR(n): return [S() for i in range(n)]
def S(): return input()
def LS(): return input().split()


INF = float('inf')


s = S()
ans = 0
w_cnt = 0
for i in range(len(s)):
    if s[i] == "W":
        ans += i - w_cnt  # その W の場所までにあった B の数
        w_cnt += 1

print(ans)

Buggy python submission (verdict: Runtime Error):
import sys


def input(): return sys.stdin.readline().strip()
def I(): return int(input())
def LI(): return list(map(int, input().split()))
def IR(n): return [I() for i in range(n)]
def LIR(n): return [LI() for i in range(n)]
def SR(n): return [S() for i in range(n)]
def S(): return input()
def LS(): return input().split()


INF = float('inf')


def calc_rle_l(s):
    now_c = s[0]
    count = 1
    res = []
    for i in range(1, len(s)):
        if now_c == s[i]:  # 同じ文字が続く
            count += 1
        else:  # 手前まで続いた文字を集計
            res.append([now_c, count])
            now_c = s[i]
            count = 1
    res.append([now_c, count])  # 最後に続く文字
    return res


s = S()
if len(set(s)) < 2:  # B か W しかない
    print(0)
    sys.exit()

rle = calc_rle_l(s)
# print(rle)
if rle[0][1] == 'W':
    rle = rle[1:]
if rle[-1] == 'B':
    rle = rle[:-1]
ans = 0
for i in range(0, len(rle), 2):
    ans += rle[i][1] * rle[i + 1][1]
    if i + 2 < len(rle):
        rle[i + 2][1] += rle[i][1]
print(ans)


Fixed submission:
import sys


def input(): return sys.stdin.readline().strip()
def I(): return int(input())
def LI(): return list(map(int, input().split()))
def IR(n): return [I() for i in range(n)]
def LIR(n): return [LI() for i in range(n)]
def SR(n): return [S() for i in range(n)]
def S(): return input()
def LS(): return input().split()


INF = float('inf')


s = S()
ans = 0
w_cnt = 0
for i in range(len(s)):
    if s[i] == "W":
        ans += i - w_cnt  # その W の場所までにあった B の数
        w_cnt += 1

print(ans)

Buggy python submission (verdict: Runtime Error):
import sys


def input(): return sys.stdin.readline().strip()
def I(): return int(input())
def LI(): return list(map(int, input().split()))
def IR(n): return [I() for i in range(n)]
def LIR(n): return [LI() for i in range(n)]
def SR(n): return [S() for i in range(n)]
def S(): return input()
def LS(): return input().split()


INF = float('inf')


def calc_rle(s):
    tmp, count, ans = s[0], 1, ""
    for i in range(1, len(s)):
        if tmp == s[i]:
            count += 1
        else:
            ans += tmp + str(count)
            tmp = s[i]
            count = 1
    ans += tmp + str(count)
    return ans


s = S()
if len(set(s)) < 2:  # B か W しかない
    print(0)
    sys.exit()

rle = calc_rle(s)

if rle[0] == 'W':
    rle = rle[2:]
if len(rle) // 2 >= 2 and rle[-2] == 'B':
    rle = rle[:-2]
# print(rle)
rle = [[rle[i], eval(rle[i+1])] for i in range(0, len(rle), 2)]
# print(rle)
ans = 0
for i in range(0, len(rle), 2):
    # print(rle[i], rle[i+1])
    ans += rle[i][1] * rle[i + 1][1]
    if i + 2 < len(rle):
        rle[i + 2][1] += rle[i][1]
    # print(f'{ans=}')
print(ans)


Fixed submission:
import sys


def input(): return sys.stdin.readline().strip()
def I(): return int(input())
def LI(): return list(map(int, input().split()))
def IR(n): return [I() for i in range(n)]
def LIR(n): return [LI() for i in range(n)]
def SR(n): return [S() for i in range(n)]
def S(): return input()
def LS(): return input().split()


INF = float('inf')


s = S()
ans = 0
w_cnt = 0
for i in range(len(s)):
    if s[i] == "W":
        ans += i - w_cnt  # その W の場所までにあった B の数
        w_cnt += 1

print(ans)

Buggy python submission (verdict: Runtime Error):
import sys


def input(): return sys.stdin.readline().strip()
def I(): return int(input())
def LI(): return list(map(int, input().split()))
def IR(n): return [I() for i in range(n)]
def LIR(n): return [LI() for i in range(n)]
def SR(n): return [S() for i in range(n)]
def S(): return input()
def LS(): return input().split()


INF = float('inf')


def calc_rle(s):
    tmp, count, ans = s[0], 1, ""
    for i in range(1, len(s)):
        if tmp == s[i]:
            count += 1
        else:
            ans += tmp + str(count)
            tmp = s[i]
            count = 1
    ans += tmp + str(count)
    return ans


s = S()
rle = calc_rle(s)
if 'W' not in s or 'B' not in s:
    print(0)
    sys.exit()
# print(rle)
if rle[0] == 'W':
    rle = rle[2:]
if len(rle) // 2 >= 2 and rle[-2] == 'B':
    rle = rle[:-2]
# print(rle)
rle = [[rle[i], eval(rle[i+1])] for i in range(0, len(rle), 2)]
# print(rle)
ans = 0
for i in range(0, len(rle), 2):
    # print(rle[i], rle[i+1])
    ans += rle[i][1] * rle[i + 1][1]
    if i + 2 < len(rle):
        rle[i + 2][1] += rle[i][1]
    # print(f'{ans=}')
print(ans)


Fixed submission:
import sys


def input(): return sys.stdin.readline().strip()
def I(): return int(input())
def LI(): return list(map(int, input().split()))
def IR(n): return [I() for i in range(n)]
def LIR(n): return [LI() for i in range(n)]
def SR(n): return [S() for i in range(n)]
def S(): return input()
def LS(): return input().split()


INF = float('inf')


s = S()
ans = 0
w_cnt = 0
for i in range(len(s)):
    if s[i] == "W":
        ans += i - w_cnt  # その W の場所までにあった B の数
        w_cnt += 1

print(ans)

Buggy python submission (verdict: Runtime Error):
import sys


def input(): return sys.stdin.readline().strip()
def I(): return int(input())
def LI(): return list(map(int, input().split()))
def IR(n): return [I() for i in range(n)]
def LIR(n): return [LI() for i in range(n)]
def SR(n): return [S() for i in range(n)]
def S(): return input()
def LS(): return input().split()


INF = float('inf')


def calc_rle(s):
    tmp, count, ans = s[0], 1, ""
    for i in range(1, len(s)):
        if tmp == s[i]:
            count += 1
        else:
            ans += tmp + str(count)
            tmp = s[i]
            count = 1
    ans += tmp + str(count)
    return ans


s = S()
rle = calc_rle(s)
if rle[0] == 'W':
    rle = rle[2:]
if len(rle)  >= 4 and rle[-2] == 'B':
    rle = rle[:-2]
rle = [[rle[i], eval(rle[i+1])] for i in range(0, len(rle), 2)]
ans = 0
for i in range(0, len(rle), 2):
    ans += rle[i][1] * rle[i + 1][1]
    if i + 2 < len(rle):
        rle[i + 2][1] += rle[i][1]
print(ans)


Fixed submission:
import sys


def input(): return sys.stdin.readline().strip()
def I(): return int(input())
def LI(): return list(map(int, input().split()))
def IR(n): return [I() for i in range(n)]
def LIR(n): return [LI() for i in range(n)]
def SR(n): return [S() for i in range(n)]
def S(): return input()
def LS(): return input().split()


INF = float('inf')


s = S()
ans = 0
w_cnt = 0
for i in range(len(s)):
    if s[i] == "W":
        ans += i - w_cnt  # その W の場所までにあった B の数
        w_cnt += 1

print(ans)

Buggy python submission (verdict: Runtime Error):
import sys


def input(): return sys.stdin.readline().strip()
def I(): return int(input())
def LI(): return list(map(int, input().split()))
def IR(n): return [I() for i in range(n)]
def LIR(n): return [LI() for i in range(n)]
def SR(n): return [S() for i in range(n)]
def S(): return input()
def LS(): return input().split()


INF = float('inf')


def calc_rle(s):
    tmp, count, ans = s[0], 1, ""
    for i in range(1, len(s)):
        if tmp == s[i]:
            count += 1
        else:
            ans += tmp + str(count)
            tmp = s[i]
            count = 1
    ans += tmp + str(count)
    return ans


s = S()
rle = calc_rle(s)
if rle[0] == 'W':
    rle = rle[2:]
if rle[-2] == 'B':
    rle = rle[:-2]
# print(rle)
rle = [[rle[i], eval(rle[i+1])] for i in range(0, len(rle), 2)]
# print(rle)
ans = 0
for i in range(0, len(rle), 2):
    # print(rle[i], rle[i+1])
    ans += rle[i][1] * rle[i + 1][1]
    if i + 2 < len(rle):
        rle[i + 2][1] += rle[i][1]
    # print(f'{ans=}')
print(ans)


Fixed submission:
import sys


def input(): return sys.stdin.readline().strip()
def I(): return int(input())
def LI(): return list(map(int, input().split()))
def IR(n): return [I() for i in range(n)]
def LIR(n): return [LI() for i in range(n)]
def SR(n): return [S() for i in range(n)]
def S(): return input()
def LS(): return input().split()


INF = float('inf')


s = S()
ans = 0
w_cnt = 0
for i in range(len(s)):
    if s[i] == "W":
        ans += i - w_cnt  # その W の場所までにあった B の数
        w_cnt += 1

print(ans)

Buggy python submission (verdict: Runtime Error):
import sys


def input(): return sys.stdin.readline().strip()
def I(): return int(input())
def LI(): return list(map(int, input().split()))
def IR(n): return [I() for i in range(n)]
def LIR(n): return [LI() for i in range(n)]
def SR(n): return [S() for i in range(n)]
def S(): return input()
def LS(): return input().split()


INF = float('inf')


def calc_rle(s):
    tmp, count, ans = s[0], 1, ""
    for i in range(1, len(s)):
        if tmp == s[i]:
            count += 1
        else:
            ans += tmp + str(count)
            tmp = s[i]
            count = 1
    ans += tmp + str(count)
    return ans


s = S()
rle = calc_rle(s)
print(rle)
if rle[0] == 'W':
    rle = rle[2:]
if rle[-2] == 'B':
    rle = rle[:-2]
# print(rle)
rle = [[rle[i], eval(rle[i+1])] for i in range(0, len(rle), 2)]
# print(rle)
ans = 0
for i in range(0, len(rle), 2):
    # print(rle[i], rle[i+1])
    ans += rle[i][1] * rle[i + 1][1]
    if i + 2 < len(rle):
        rle[i + 2][1] += rle[i][1]
    # print(f'{ans=}')
print(ans)


Fixed submission:
import sys


def input(): return sys.stdin.readline().strip()
def I(): return int(input())
def LI(): return list(map(int, input().split()))
def IR(n): return [I() for i in range(n)]
def LIR(n): return [LI() for i in range(n)]
def SR(n): return [S() for i in range(n)]
def S(): return input()
def LS(): return input().split()


INF = float('inf')


s = S()
ans = 0
w_cnt = 0
for i in range(len(s)):
    if s[i] == "W":
        ans += i - w_cnt  # その W の場所までにあった B の数
        w_cnt += 1

print(ans)