Problem: K Average Ranges

Given the sequence a_1, a_2, .., a_N.

How many intervals in this sequence have an average value of K or more and a length of 1 or more?

input


N K
a_1 a_2 ... a_N


output

Output the answer.

Constraint

* 1 \ leq N \ leq 10 ^ 5
* 1 \ leq K \ leq 10 ^ 9
* 1 \ leq a_i \ leq 10 ^ 9



Input example


6 6
8 6 9 1 2 1


Output example


7






Example

Input

6 6
8 6 9 1 2 1


Output

7

Solution (in CPP):

Solution:
#include <bits/stdc++.h>
#define pb push_back
#define eb emplace_back
#define fi first
#define se second
#define rep(i,N) for(long long i = 0; i < (long long)(N); i++)
#define repr(i,N) for(long long i = (long long)(N) - 1; i >= 0; i--)
#define rep1(i,N) for(long long i = 1; i <= (long long)(N) ; i++)
#define repr1(i,N) for(long long i = (N) ; (long long)(i) > 0 ; i--)
#define each(x,v) for(auto& x : v)
#define all(v) (v).begin(),(v).end()
#define sz(v) ((int)(v).size())
#define ini(...) int __VA_ARGS__; in(__VA_ARGS__)
#define inl(...) long long __VA_ARGS__; in(__VA_ARGS__)
#define ins(...) string __VA_ARGS__; in(__VA_ARGS__)
using namespace std; void solve();
using ll = long long; template<class T = ll> using V = vector<T>;
using vi = V<int>; using vl = V<>; using vvi = V< V<int> >;
constexpr int inf = 1001001001; constexpr ll infLL = (1LL << 61) - 1;
struct IoSetupNya {IoSetupNya() { cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(15); cerr << fixed << setprecision(7);} } iosetupnya;
template<typename T, typename U> inline bool amin(T &x, U y) { return (y < x) ? (x = y, true) : false; }
template<typename T, typename U> inline bool amax(T &x, U y) { return (x < y) ? (x = y, true) : false; }
template<typename T, typename U> ostream& operator <<(ostream& os, const pair<T, U> &p) { os << p.first << " " << p.second; return os; }
template<typename T, typename U> istream& operator >>(istream& is, pair<T, U> &p) { is >> p.first >> p.second; return is; }
template<typename T> ostream& operator <<(ostream& os, const vector<T> &v) { int s = (int)v.size(); rep(i,s) os << (i ? " " : "") << v[i]; return os; }
template<typename T> istream& operator >>(istream& is, vector<T> &v) { for(auto &x : v) is >> x; return is; }
void in(){} template <typename T,class... U> void in(T &t,U &...u){ cin >> t; in(u...);}
void out(){cout << "\n";} template <typename T,class... U> void out(const T &t,const U &...u){ cout << t; if(sizeof...(u)) cout << " "; out(u...);}
template<typename T>void die(T x){out(x); exit(0);}
#ifdef NyaanDebug
  #include "NyaanDebug.h"
  #define trc(...) do { cerr << #__VA_ARGS__ << " = "; dbg_out(__VA_ARGS__);} while(0)
  #define trca(v,N) do { cerr << #v << " = "; array_out(v , N);cout << endl;} while(0)
#else
  #define trc(...)
  #define trca(...)
  int main(){solve();}
#endif

using P = pair<ll,ll>; using vp = V<P>;
constexpr int MOD = /**/ 1000000007; //*/ 998244353;
//////////

// BIT

template< typename T >
struct BIT {
  int N; int max_2beki;

  vector< T > data;
  // 初期化 1-indexedでデータを管理する 0で初期化
  BIT(int size){
      N = ++size;
      data.assign(N, 0);
      max_2beki = 1;
      while(max_2beki * 2 <= N) max_2beki *= 2;
  }

  // [0,k](閉区間)の総和 閉区間に注意！
  T sum(int k) {
    if(k < 0) return 0; // k<0のとき0を返す
    T ret = 0;
    for(++k; k > 0; k -= k & -k) ret += data[k];
    return (ret);
  }

  // [l,r](閉区間)の総和
  inline T sum(int l,int r){
    return sum(r) - sum(l-1);
  }

  // 一点取得 更新はできないことに注意
  inline T operator[](int k){
    return sum(k) - sum(k-1);
  }

  // data[k] += x;
  void add(int k, T x) {
    for(++k; k < N; k += k & -k) data[k] += x;
  }

  // imos法 [l,r]にxを加算
  void imos(int l,int r,T x){
    add(l , x); add(r + 1 , -x);
  }

  // lower_bound sum(i)がval以上となる最小のi
  int lower_bound(T w){
    if(w <= 0) return 0;
    int x = 0;
    for(int k = max_2beki; k > 0; k /= 2){
      if(x+k <= N - 1 && data[x + k] < w){
        w -= data[x + k];
        x += k;
      }
    }
    return x;
  }

  // upper_bound sum(i)がvalより大きくなる最小のi
  int upper_bound(T w){
    if(w < 0) return 0;
    int x = 0;
    for(int k = max_2beki; k > 0; k /= 2){
      if(x+k <= N - 1 && data[x + k] <= w){
        w -= data[x + k];
        x += k;
      }
    }
    return x;
  }

};

template<class T>
struct compress{
  vector<T> xs;
  compress(const vector<T>& v){
    xs.reserve(v.size());
    for(T x : v) xs.push_back(x);
    sort(xs.begin(),xs.end());
    xs.erase(unique(xs.begin(),xs.end()) , xs.end());
  }

  int get(const T& x){
    return lower_bound(xs.begin(),xs.end(),x) - xs.begin();
  }
  int size(){
    return xs.size();
  }
  T& operator[](int i){
    return xs[i];
  }
};

void solve(){
  ini(N); inl(K);
  vl a(N); in(a);
  each(x , a) x -= K;
  // ruiseki
  vl rui(N + 1);
  rep1(i , N) rui[i] = rui[i - 1] + a[i - 1];
  
  compress<ll> zip(rui);
  BIT<ll> bit(zip.size() + 10);

  ll ans = 0;

  // iに対して i < j <= Nについてrui[j]を取ると
  // rui[j] - rui[i]が[i , j)の値
  // -> iについてi < j <= Nの範囲において
  // rui[j] >= rui[i]を満たすjの個数を数えればよい

  repr(i , N){
    bit.add(zip.get(rui[i + 1]) , 1);
    ans += bit.sum(zip.get(rui[i]) , zip.size());
  }

  out(ans);
  
  


}