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


def get_result(data):
    # N = int(data[0][0])
    S = data[1][0]
    r_index = [i for i in range(len(S)) if S[i] == 'R']
    g_index = [i for i in range(len(S)) if S[i] == 'G']
    b_index = [i for i in range(len(S)) if S[i] == 'B']
    all_case = len(r_index) * len(g_index) * len(b_index)
    invalid_case = 0
    for i in r_index:
        for j in g_index:
            s_i, s_j = sorted([i, j])
            tmp_max_b = s_j + (s_j-s_i)
            if tmp_max_b in b_index:
                invalid_case += 1
            tmp_min_b = s_i - (s_j-s_i)
            if tmp_min_b in b_index:
                invalid_case += 1
            tmp_mid_b = (s_i + s_j) / 2
            if tmp_mid_b in b_index:
                invalid_case += 1
    return all_case - invalid_case


if __name__ == '__main__':
    raw_data = [val.rstrip() for val in stdin.readlines()]
    data = [list(map(str, val.split(' '))) for val in raw_data]
    result = get_result(data)
    print(result)


Fixed submission:
from sys import stdin


def get_result(data):
    # N = int(data[0][0])
    S = data[1][0]
    r_index = [i for i in range(len(S)) if S[i] == 'R']
    g_index = [i for i in range(len(S)) if S[i] == 'G']
    b_index = set([i for i in range(len(S)) if S[i] == 'B'])
    all_case = len(r_index) * len(g_index) * len(b_index)
    invalid_case = 0
    for i in r_index:
        for j in g_index:
            s_i, s_j = sorted([i, j])
            tmp_max_b = s_j + (s_j-s_i)
            if tmp_max_b in b_index:
                invalid_case += 1
            tmp_min_b = s_i - (s_j-s_i)
            if tmp_min_b in b_index:
                invalid_case += 1
            tmp_mid_b = (s_i + s_j) / 2
            if tmp_mid_b in b_index:
                invalid_case += 1
    return all_case - invalid_case


if __name__ == '__main__':
    raw_data = [val.rstrip() for val in stdin.readlines()]
    data = [list(map(str, val.split(' '))) for val in raw_data]
    result = get_result(data)
    print(result)

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


def get_result(data):
    # N = int(data[0][0])
    S = data[1][0]
    r_index = [i for i in range(len(S)) if S[i] == 'R']
    g_index = [i for i in range(len(S)) if S[i] == 'G']
    b_index = [i for i in range(len(S)) if S[i] == 'B']
    all_case = len(r_index) * len(g_index) * len(b_index)
    invalid_case = 0
    for i in r_index:
        for j in g_index:
            s_i, s_j = sorted([i, j])
            tmp_max_b = s_j + (s_j-s_i)
            if tmp_max_b in b_index:
                invalid_case += 1
            tmp_min_b = s_i - (s_j-s_i)
            if tmp_min_b in b_index:
                invalid_case += 1
            tmp_mid_b = (s_i + s_j) / 2
            if tmp_mid_b in b_index:
                invalid_case += 1
    return all_case - invalid_case


if __name__ == '__main__':
    raw_data = [val.rstrip() for val in stdin.readlines()]
    data = [list(map(str, val.split(' '))) for val in raw_data]
    result = get_result(data)
    print(result)


Fixed submission:
from sys import stdin


def get_result(data):
    # N = int(data[0][0])
    S = data[1][0]
    r_index = [i for i in range(len(S)) if S[i] == 'R']
    g_index = [i for i in range(len(S)) if S[i] == 'G']
    b_index = set([i for i in range(len(S)) if S[i] == 'B'])
    all_case = len(r_index) * len(g_index) * len(b_index)
    invalid_case = 0
    for i in r_index:
        for j in g_index:
            s_i, s_j = sorted([i, j])
            tmp_max_b = s_j + (s_j-s_i)
            if tmp_max_b in b_index:
                invalid_case += 1
            tmp_min_b = s_i - (s_j-s_i)
            if tmp_min_b in b_index:
                invalid_case += 1
            tmp_mid_b = (s_i + s_j) / 2
            if tmp_mid_b in b_index:
                invalid_case += 1
    return all_case - invalid_case


if __name__ == '__main__':
    raw_data = [val.rstrip() for val in stdin.readlines()]
    data = [list(map(str, val.split(' '))) for val in raw_data]
    result = get_result(data)
    print(result)

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


def get_result(data):
    # N = int(data[0][0])
    S = data[1][0]
    ans = 0
    r_index = [i for i in range(len(S)) if S[i] == 'R']
    g_index = [i for i in range(len(S)) if S[i] == 'G']
    b_index = [i for i in range(len(S)) if S[i] == 'B']
    for i in r_index:
        for j in g_index:
            for k in b_index:
                s_i, s_j, s_k = sorted([i, j, k])
                if (s_j-s_i) != (s_k-s_j):
                    ans += 1
    return ans


if __name__ == '__main__':
    raw_data = [val.rstrip() for val in stdin.readlines()]
    data = [list(map(str, val.split(' '))) for val in raw_data]
    result = get_result(data)
    print(result)


Fixed submission:
from sys import stdin


def get_result(data):
    # N = int(data[0][0])
    S = data[1][0]
    r_index = [i for i in range(len(S)) if S[i] == 'R']
    g_index = [i for i in range(len(S)) if S[i] == 'G']
    b_index = set([i for i in range(len(S)) if S[i] == 'B'])
    all_case = len(r_index) * len(g_index) * len(b_index)
    invalid_case = 0
    for i in r_index:
        for j in g_index:
            s_i, s_j = sorted([i, j])
            tmp_max_b = s_j + (s_j-s_i)
            if tmp_max_b in b_index:
                invalid_case += 1
            tmp_min_b = s_i - (s_j-s_i)
            if tmp_min_b in b_index:
                invalid_case += 1
            tmp_mid_b = (s_i + s_j) / 2
            if tmp_mid_b in b_index:
                invalid_case += 1
    return all_case - invalid_case


if __name__ == '__main__':
    raw_data = [val.rstrip() for val in stdin.readlines()]
    data = [list(map(str, val.split(' '))) for val in raw_data]
    result = get_result(data)
    print(result)

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


def get_result(data):
    N = int(data[0][0])
    S = data[1][0]
    ans = 0
    for i in range(N-2):
        for j in range(i+1, N-1):
            if S[i] != S[j]:
                for k in range(j+1, N):
                    if S[j] != S[k] and S[k] != S[i]:
                        if (j-i) != (k-j):
                            ans += 1
    return ans


if __name__ == '__main__':
    raw_data = [val.rstrip() for val in stdin.readlines()]
    data = [list(map(str, val.split(' '))) for val in raw_data]
    result = get_result(data)
    print(result)


Fixed submission:
from sys import stdin


def get_result(data):
    # N = int(data[0][0])
    S = data[1][0]
    r_index = [i for i in range(len(S)) if S[i] == 'R']
    g_index = [i for i in range(len(S)) if S[i] == 'G']
    b_index = set([i for i in range(len(S)) if S[i] == 'B'])
    all_case = len(r_index) * len(g_index) * len(b_index)
    invalid_case = 0
    for i in r_index:
        for j in g_index:
            s_i, s_j = sorted([i, j])
            tmp_max_b = s_j + (s_j-s_i)
            if tmp_max_b in b_index:
                invalid_case += 1
            tmp_min_b = s_i - (s_j-s_i)
            if tmp_min_b in b_index:
                invalid_case += 1
            tmp_mid_b = (s_i + s_j) / 2
            if tmp_mid_b in b_index:
                invalid_case += 1
    return all_case - invalid_case


if __name__ == '__main__':
    raw_data = [val.rstrip() for val in stdin.readlines()]
    data = [list(map(str, val.split(' '))) for val in raw_data]
    result = get_result(data)
    print(result)

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


def get_result(data):
    N = int(data[0][0])
    S = data[1][0]
    ans = 0
    for i in range(N-2):
        for j in range(i, N-1):
            for k in range(j, N):
                if (j-i) != (k-j):
                    if S[i] != S[j] and S[j] != S[k] and S[k] != S[i]:
                        ans += 1
    return ans


if __name__ == '__main__':
    raw_data = [val.rstrip() for val in stdin.readlines()]
    data = [list(map(str, val.split(' '))) for val in raw_data]
    result = get_result(data)
    print(result)


Fixed submission:
from sys import stdin


def get_result(data):
    # N = int(data[0][0])
    S = data[1][0]
    r_index = [i for i in range(len(S)) if S[i] == 'R']
    g_index = [i for i in range(len(S)) if S[i] == 'G']
    b_index = set([i for i in range(len(S)) if S[i] == 'B'])
    all_case = len(r_index) * len(g_index) * len(b_index)
    invalid_case = 0
    for i in r_index:
        for j in g_index:
            s_i, s_j = sorted([i, j])
            tmp_max_b = s_j + (s_j-s_i)
            if tmp_max_b in b_index:
                invalid_case += 1
            tmp_min_b = s_i - (s_j-s_i)
            if tmp_min_b in b_index:
                invalid_case += 1
            tmp_mid_b = (s_i + s_j) / 2
            if tmp_mid_b in b_index:
                invalid_case += 1
    return all_case - invalid_case


if __name__ == '__main__':
    raw_data = [val.rstrip() for val in stdin.readlines()]
    data = [list(map(str, val.split(' '))) for val in raw_data]
    result = get_result(data)
    print(result)