void Calc()
{
int N = re.i();
int[] white = new int[N];
int[] black = new int[N];
for (int i = 0; i < 2 * N; i++)
{
if (re.s() == "W")
{
white[re.i() - 1] = i;
}
else
{
black[re.i() - 1] = i;
}
}
long[,] DP = new long[N + 1, N + 1];
for (int i = 0; i <= N; i++)
{
SegTree Seg = new SegTree(2 * N, this);
for (int j = 0; j < i; j++)
{
Seg.Add(white[j]);
}
for (int j = 0; j <= N; j++)
{
if (i == 0 & j == 0)
{
DP[i, j] = 0;
}
else if (i == 0)
{
DP[i, j] = DP[i, j - 1] + Seg.Sum(black[j - 1] + 1, 2 * N - 1);
Seg.Add(black[j - 1]);
}
else if (j == 0)
{
DP[i, j] = DP[i - 1, j] + Seg.Sum(white[i - 1] + 1, 2 * N - 1);
}
else
{
Seg.Add(black[j - 1]);
DP[i, j] = Math.Min(DP[i - 1, j] + Seg.Sum(white[i - 1] + 1, 2 * N - 1), DP[i, j - 1] + Seg.Sum(black[j - 1] + 1, 2 * N - 1));
}
}
}
sb.Append(DP[N, N] + "\n");
}
void Calc()
{
string[] str = Console.ReadLine().Split(' ');
int N = int.Parse(str[0]);
long K = int.Parse(str[1]);
long[] A = new long[N];
for (int i = 0; i < N; i++)
{
A[i] = int.Parse(Console.ReadLine()) - K;
}
N++;
long[] sum = new long[N];
for (int i = 1; i < N; i++)
{
sum[i] = sum[i - 1] + A[i - 1];
}
long[] B = new long[N];
int[] C = new int[N];
for (int i = 0; i < N; i++)
{
B[i] = sum[i];
C[i] = i;
}
Array.Sort(C, (x, y) => (B[x] > B[y] ? 1 : (B[x] == B[y] ? (x > y ? 1 : (x == y ? 0 : -1)) : -1)));
SegTree Seg = new SegTree(N, this);
long count = 0;
for (int i = N - 1; i >= 0; i--)
{
count += Seg.Sum(C[i], N - 1);
Seg.Add(C[i]);
}
sb.Append(count + "\n");
}
void Calc()
{
string S = re.s();
int N = S.Length;
int[] C = new int[26];
for (int i = 0; i < N; i++)
{
C[S[i] - 'a']++;
}
int odd = 0;
for (int i = 0; i < 26; i++)
{
if (C[i] % 2 == 1)
{
odd++;
}
}
if (odd > 1 || (odd == 1 && N % 2 == 0))
{
sb.Append(-1 + "\n");
return;
}
List <int>[] G = new List <int> [26];
for (int i = 0; i < 26; i++)
{
G[i] = new List <int>();
}
int[] order = new int[N];
for (int i = 0; i < N; i++)
{
order[i] = G[S[i] - 'a'].Count;
G[S[i] - 'a'].Add(i);
}
SegTree Seg = new SegTree(N, this);
for (int i = 2 * N - 2; i >= 0; i--)
{
if (i >= Seg.segf)
{
Seg.X[i] = 1;
}
else
{
int sl = i * 2 + 1;
int sr = i * 2 + 2;
Seg.X[i] = Seg.X[sl] + Seg.X[sr];
}
}
long count = 0;
bool center = false;
for (int i = 0; i < N; i++)
{
if (order[i] * 2 + 1 < C[S[i] - 'a'])
{
int pair = G[S[i] - 'a'][C[S[i] - 'a'] - 1 - order[i]];
if (pair != N - 1)
{
count += Seg.Sum(pair + 1, N - 1);
}
Seg.Delete(pair);
if (center)
{
count++;
}
}
else if (order[i] * 2 + 1 == C[S[i] - 'a'])
{
center = true;
}
}
sb.Append(count + "\n");
}