// clang-format off
#include <bits/stdc++.h>

using namespace std;

#if __cplusplus < 201400
  #warning "Please use c++14 or higher."
  #define INLINE_V
  #define REGISTER_V register
  #define CPP14CONSTEXPR
  #define gcd __gcd
  #define CPP14ENABLE_IF
#elif __cplusplus < 201700
  #define INLINE_V
  #define REGISTER_V
  #define CPP14CONSTEXPR constexpr
  #define gcd __gcd
  #define CPP14ENABLE_IF ,enable_if_t<_is_integer<T>, int> = 0
#else
  #define INLINE_V inline
  #define REGISTER_V
  #define CPP14CONSTEXPR constexpr
  #define CPP14ENABLE_IF ,enable_if_t<_is_integer<T>, int> = 0
#endif

#if !defined(_WIN32) && !defined(LOCK_GETCHAR)
  #define getchar getchar_unlocked
#endif

#define il inline
#define mkp make_pair
#define fi first
#define se second
#define For(i,j,k) for(REGISTER_V int i=(j);i<=(k);++i) // NOLINT
#define ForDown(i,j,k) for(REGISTER_V int i=(j);i>=(k);--i) // NOLINT
#define pb push_back
#define eb emplace_back
#ifndef ONLINE_JUDGE
#define FileIO(filename) freopen(filename".in","r",stdin);freopen(filename".out","w",stdout)
#else
#define FileIO(filename)
#endif

using ll = long long;
// using lll = __int128_t;
using uint = unsigned int;
using ull = unsigned long long;
// using ulll = __uint128_t;
using db = double;
using ldb = long double;
using pii = pair<int, int>;
using pll = pair<ll, ll>;

#if __cplusplus >= 201400
  template <class T> INLINE_V constexpr bool _is_integer = numeric_limits<T>::is_integer;
  // template <> INLINE_V constexpr bool _is_integer<__int128> = true;
  // template <> INLINE_V constexpr bool _is_integer<__uint128_t> = true;
  template <> INLINE_V constexpr bool _is_integer<bool> = false;
  template <> INLINE_V constexpr bool _is_integer<char> = false;
  template <class T CPP14ENABLE_IF>
    INLINE_V constexpr T INF = numeric_limits<T>::max() >> 1;
#endif

template<typename T> constexpr il T sq(const T & x){return x*x;}
template<typename T> CPP14CONSTEXPR il void cmin(T & x, const T &y){x=min(x,y);}
template<typename T> CPP14CONSTEXPR il void cmax(T & x, const T &y){x=max(x,y);}
template<typename T> CPP14CONSTEXPR il T qpow(T x, ull y, T mod){T ans=1;x%=mod;while(y){if(y&1)(ans*=x)%=mod;(x*=x)%=mod;y>>=1;}return ans;}
template<typename T> CPP14CONSTEXPR il T qpow(T x, ull y){T ans=1;while(y){if(y&1)ans*=x;x*=x;y>>=1;}return ans;}
template<typename T CPP14ENABLE_IF> il void read(T &x){ x=0;int f=1;int c=getchar();while(!isdigit(c)){if(c=='-')f=-1;c=getchar();}while(isdigit(c)){x=x*10+c-'0';c=getchar();}x*=f;}
template<typename T, typename ... Args> il void read(T &x, Args &... y){ read(x);read(y...); }

// File head end
// clang-format on

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace __gnu_pbds;
using bst = __gnu_pbds::tree<pair<ll, int>, null_type, less<>, rb_tree_tag,
                             tree_order_statistics_node_update>;

namespace {
constexpr ll MAXN = 1e6 + 5;
int n, E;
pii a[MAXN];
ll sum[MAXN];

struct Node {
  int l, r;
  ll minv, tag;
  Node() : l(0), r(0), minv(1e18), tag(0) {}
} T[MAXN << 1];
#define mid(p) ((T[p].l + T[p].r) >> 1)
#define lc(p) (mid(p) << 1)
#define rc(p) (mid(p) << 1 | 1)
il void pu(int p) { T[p].minv = min(T[lc(p)].minv, T[rc(p)].minv); }
il void f(int p, ll tg) { assert(p), T[p].minv += tg, T[p].tag += tg; }
il void pd(int p) {
  f(lc(p), T[p].tag);
  f(rc(p), T[p].tag);
  T[p].tag = 0;
}
void build(int p, int l, int r) {
  T[p].l = l, T[p].r = r;
  if (l == r)
    return T[p].minv = E - a[l].fi, void();
  build(lc(p), l, mid(p)), build(rc(p), mid(p) + 1, r);
  pu(p);
}
void add(int p, int ql, int qr, int val) {
  int l = T[p].l, r = T[p].r;
  if (ql <= l && qr >= r)
    return f(p, val);
  pd(p);
  if (ql <= mid(p))
    add(lc(p), ql, qr, val);
  if (qr > mid(p))
    add(rc(p), ql, qr, val);
  pu(p);
}
ll qry(int p, int ql, int qr) {
  int l = T[p].l, r = T[p].r;
  if (ql <= l && qr >= r)
    return T[p].minv;
  pd(p);
  ll ans = 1e18;
  if (ql <= mid(p))
    cmin(ans, qry(lc(p), ql, qr));
  if (qr > mid(p))
    cmin(ans, qry(rc(p), ql, qr));
  return ans;
}

bst st;
ll Cur = 0;
il bool ok(int l, int r) {
  // if (l < r)
  //   cerr << "> " << l << ' ' << r << ' ' << qry(1, l, r - 1) << '\n';
  return l >= r ||
         (qry(1, l, r - 1) >= a[r].fi - a[r].se && E - a[r].fi >= Cur);
}
il void ins(int l, int pos) {
  add(1, pos, pos, -Cur);
  if (a[pos].se < a[pos].fi) {
    Cur += a[pos].fi - a[pos].se;
    if (l < pos)
      add(1, l, pos - 1, a[pos].se - a[pos].fi);
  }
  st.insert(mkp(sum[pos], pos));
}
il void del(int pos, int r) {
  if (a[pos].se < a[pos].fi) {
    Cur -= a[pos].fi - a[pos].se;
    if (pos < r)
      add(1, pos + 1, r, a[pos].fi - a[pos].se);
  }
  st.erase(mkp(sum[pos], pos));
}

il void solver_main() {
  read(n, E);
  For(i, 1, n) read(a[i].fi);
  For(i, 1, n) read(a[i].se);
  For(i, 1, n) sum[i] = sum[i - 1] + a[i].se - a[i].fi;
  build(1, 1, n);

  ll cnt = 0;
  for (int i = 1, j = 0; i <= n; i++) {
    while (j + 1 <= n && ok(i, j + 1))
      j++, ins(i, j);
    cnt += st.size() - st.order_of_key(mkp(sum[i - 1], n + 5));
    del(i, j);
    // cerr << i << ' ' << j << ' ' << Cur << ' ' << qry(1, 3, 3) << '\n';
  }
  cout << cnt << '\n';
}
} // namespace

signed main() { return solver_main(), 0; }