During a break in the buffet of the scientific lyceum of the Kingdom of Kremland, there was formed a queue of n high school students numbered from 1 to n. Initially, each student i is on position i. Each student i is characterized by two numbers — a_i and b_i. Dissatisfaction of the person i equals the product of a_i by the number of people standing to the left of his position, add the product b_i by the number of people standing to the right of his position. Formally, the dissatisfaction of the student i, which is on the position j, equals a_i ⋅ (j-1) + b_i ⋅ (n-j).

The director entrusted Stas with the task: rearrange the people in the queue so that minimize the total dissatisfaction.

Although Stas is able to solve such problems, this was not given to him. He turned for help to you.

Input

The first line contains a single integer n (1 ≤ n ≤ 10^5) — the number of people in the queue.

Each of the following n lines contains two integers a_i and b_i (1 ≤ a_i, b_i ≤ 10^8) — the characteristic of the student i, initially on the position i.

Output

Output one integer — minimum total dissatisfaction which can be achieved by rearranging people in the queue.

Examples

Input


3
4 2
2 3
6 1


Output


12

Input


4
2 4
3 3
7 1
2 3


Output


25

Input


10
5 10
12 4
31 45
20 55
30 17
29 30
41 32
7 1
5 5
3 15


Output


1423

Note

In the first example it is optimal to put people in this order: (3, 1, 2). The first person is in the position of 2, then his dissatisfaction will be equal to 4 ⋅ 1+2 ⋅ 1=6. The second person is in the position of 3, his dissatisfaction will be equal to 2 ⋅ 2+3 ⋅ 0=4. The third person is in the position of 1, his dissatisfaction will be equal to 6 ⋅ 0+1 ⋅ 2=2. The total dissatisfaction will be 12.

In the second example, you need to put people in this order: (3, 2, 4, 1). The total dissatisfaction will be 25.
#include <bits/stdc++.h>
using namespace std;
const int MOD = 998244353;
using ll = long long;
using ld = long double;
using db = long double;
using str = string;
using pi = pair<int, int>;
using pl = pair<ll, ll>;
using pd = pair<double, double>;
using vi = vector<int>;
using vb = vector<bool>;
using vl = vector<ll>;
using vd = vector<double>;
using vs = vector<string>;
using vpi = vector<pi>;
using vpl = vector<pl>;
using vpd = vector<pd>;
template <typename A, typename B>
pair<A, B>& operator++(pair<A, B>& a) {
  ++a.second;
  ++a.first;
  return a;
}
template <typename A, typename B>
pair<A, B>& operator--(pair<A, B>& a) {
  --a.first;
  --a.second;
  return a;
}
template <typename A>
vector<A>& operator++(vector<A>& a) {
  for (auto it = a.begin(); it != a.end(); ++it) ++*it;
  return a;
}
template <typename A>
vector<A>& operator--(vector<A>& a) {
  for (auto it = a.begin(); it != a.end(); ++it) --*it;
  return a;
}
const int di[4] = {-1, 0, 1, 0}, dj[4] = {0, 1, 0, -1};
const int di8[8] = {-1, -1, 0, 1, 1, 1, 0, -1},
          dj8[8] = {0, 1, 1, 1, 0, -1, -1, -1};
const ld PI = acos((ld)-1);
const ll INF = 1e18;
const double eps = 1e-11;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
ll randint(ll a, ll b) { return uniform_int_distribution<ll>(a, b)(rng); }
using ul = unsigned long long;
ul modMul(ul a, ul b, const ul mod) {
  ll ret = a * b - mod * (ul)((ld)a * b / mod);
  return ret + ((ret < 0) - (ret >= (ll)mod)) * mod;
}
ul modPow(ul a, ul b, const ul mod) {
  if (b == 0) return 1;
  ul res = modPow(a, b / 2, mod);
  res = modMul(res, res, mod);
  return b & 1 ? modMul(res, a, mod) : res;
}
bool pow2(int i) { return i && (i & -i) == i; }
constexpr int pct(int x) { return __builtin_popcount(x); }
constexpr int bits(int x) { return 31 - __builtin_clz(x); }
ll cdiv(ll a, ll b) { return a / b + ((a ^ b) > 0 && a % b); }
ll fdiv(ll a, ll b) { return a / b - ((a ^ b) < 0 && a % b); }
ll half(ll x) { return fdiv(x, 2); }
bool inc(ll a, ll b, ll c) { return a <= b && b <= c; }
template <class t>
int lwb(const vector<t>& v, const t& a) {
  return lower_bound((v).begin(), (v).end(), a) - v.begin();
}
template <class T>
bool chmin(T& a, const T& b) {
  return b < a ? a = b, 1 : 0;
}
template <class T>
bool chmax(T& a, const T& b) {
  return a < b ? a = b, 1 : 0;
}
void TIME() {}
template <class T>
void remDup(vector<T>& v) {
  sort((v).begin(), (v).end());
  v.erase(unique((v).begin(), (v).end()), end(v));
}
template <class T, class U>
void remAll(vector<T>& v, U a) {
  v.erase(remove((v).begin(), (v).end(), a), v.end());
}
template <class T, class U>
T fstTrue(T lo, T hi, U f) {
  while (lo < hi) {
    T mid = half(lo + hi);
    f(mid) ? hi = mid : lo = mid + 1;
  }
  return lo;
}
template <class T, class U>
T lstTrue(T lo, T hi, U f) {
  while (lo < hi) {
    T mid = half(lo + hi + 1);
    f(mid) ? lo = mid : hi = mid - 1;
  }
  return lo;
}
template <typename I>
struct _reversed_struct {
  I& v_;
  explicit _reversed_struct(I& v) : v_{v} {}
  typename I::reverse_iterator begin() const { return v_.rbegin(); }
  typename I::reverse_iterator end() const { return v_.rend(); }
};
template <typename I>
_reversed_struct<I> reversed(I& v) {
  return _reversed_struct<I>(v);
}
string to_string(char c) { return string(1, c); }
string to_string(bool b) { return to_string((int)b); }
string to_string(const char* s) { return (string)s; }
string to_string(string s) { return s; }
template <class T>
string to_string(complex<T> c) {
  stringstream ss;
  ss << c;
  return ss.str();
}
string to_string(vb v) {
  string res = "{";
  for (int i = (0); i < (((int)(v).size())); ++i) res += char('0' + v[i]);
  res += "}";
  return res;
}
template <size_t SZ>
string to_string(bitset<SZ> b) {
  string res = "";
  for (int i = (0); i < (((int)(b).size())); ++i) res += char('0' + b[i]);
  return res;
}
template <class T, class U>
string to_string(pair<T, U> p);
template <class T>
string to_string(T v) {
  bool fst = 1;
  string res = "";
  for (const auto& x : v) {
    if (!fst) res += " ";
    fst = 0;
    res += to_string(x);
  }
  return res;
}
template <class T, class U>
string to_string(pair<T, U> p) {
  return to_string(p.first) + " " + to_string(p.second);
}
template <class T>
void re(complex<T>& c);
template <class T, class U>
void re(pair<T, U>& p);
template <class T>
void re(vector<T>& v);
template <class T>
void rv(int n, vector<T>& x) {
  x.resize(n);
  re(x);
}
template <class T, size_t SZ>
void re(array<T, SZ>& a);
template <class T>
void re(T& x) {
  cin >> x;
}
void re(double& d) {
  string t;
  re(t);
  d = stod(t);
}
void re(ld& d) {
  string t;
  re(t);
  d = stold(t);
}
template <class T, class... U>
void re(T& t, U&... u) {
  re(t);
  re(u...);
}
template <class T>
void re(complex<T>& c) {
  T a, b;
  re(a, b);
  c = {a, b};
}
template <class T, class U>
void re(pair<T, U>& p) {
  re(p.first, p.second);
}
template <class T>
void re(vector<T>& x) {
  for (auto& a : x) re(a);
}
template <class T, size_t SZ>
void re(array<T, SZ>& x) {
  for (auto& a : x) re(a);
}
template <class T>
void pr(T x) {
  cout << to_string(x);
}
template <class T, class... U>
void pr(const T& t, const U&... u) {
  pr(t);
  pr(u...);
}
void ps() { pr("\n"); }
template <class T, class... U>
void ps(const T& t, const U&... u) {
  pr(t);
  if (sizeof...(u)) pr(" ");
  ps(u...);
}
struct chash {
  static uint64_t splitmix64(uint64_t x) {
    x += 0x9e3779b97f4a7c15;
    x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
    x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
    return x ^ (x >> 31);
  }
  size_t operator()(uint64_t x) const {
    static const uint64_t FIXED_RANDOM =
        chrono::steady_clock::now().time_since_epoch().count();
    return splitmix64(x + FIXED_RANDOM);
  }
  template <typename L, typename R>
  size_t operator()(pair<L, R> const& Y) const {
    static const uint64_t FIXED_RANDOM =
        chrono::steady_clock::now().time_since_epoch().count();
    return splitmix64(Y.first * 31 + Y.second + FIXED_RANDOM);
  }
};
template <class T>
using V = vector<T>;
template <class T, size_t SZ>
using AR = array<T, SZ>;
template <class T>
using mpq = priority_queue<T, vector<T>, greater<T>>;
template <class T>
using pq = priority_queue<T>;
template <class T>
using ms = multiset<T>;
template <class T, class U>
using um = unordered_map<T, U, chash>;
template <class T>
using us = unordered_set<T, chash>;
template <class T>
using PR = pair<T, T>;
template <int MOD, int RT>
struct mint {
  static const int mod = MOD;
  static constexpr mint rt() { return RT; }
  int v;
  explicit operator int() const { return v; }
  mint() { v = 0; }
  mint(ll _v) {
    v = (-MOD < _v && _v < MOD) ? _v : _v % MOD;
    if (v < 0) v += MOD;
  }
  friend bool operator==(const mint& a, const mint& b) { return a.v == b.v; }
  friend bool operator!=(const mint& a, const mint& b) { return !(a == b); }
  friend bool operator<(const mint& a, const mint& b) { return a.v < b.v; }
  friend void re(mint& a) {
    ll x;
    re(x);
    a = mint(x);
  }
  friend string to_string(mint a) { return to_string(a.v); }
  mint& operator+=(const mint& m) {
    if ((v += m.v) >= MOD) v -= MOD;
    return *this;
  }
  mint& operator-=(const mint& m) {
    if ((v -= m.v) < 0) v += MOD;
    return *this;
  }
  mint& operator*=(const mint& m) {
    v = (ll)v * m.v % MOD;
    return *this;
  }
  mint& operator/=(const mint& m) { return (*this) *= inv(m); }
  friend mint pow(mint a, ll p) {
    mint ans = 1;
    assert(p >= 0);
    for (; p; p /= 2, a *= a)
      if (p & 1) ans *= a;
    return ans;
  }
  friend mint inv(const mint& a) {
    assert(a.v != 0);
    return pow(a, MOD - 2);
  }
  mint operator-() const { return mint(-v); }
  mint& operator++() { return *this += 1; }
  mint& operator--() { return *this -= 1; }
  friend mint operator+(mint a, const mint& b) { return a += b; }
  friend mint operator-(mint a, const mint& b) { return a -= b; }
  friend mint operator*(mint a, const mint& b) { return a *= b; }
  friend mint operator/(mint a, const mint& b) { return a /= b; }
};
typedef mint<MOD, 5> mi;
vi invs, fac, ifac;
void genFac(int SZ) {
  invs.resize(SZ), fac.resize(SZ), ifac.resize(SZ);
  invs[1] = fac[0] = ifac[0] = 1;
  for (int i = (2); i < (SZ); ++i)
    invs[i] = MOD - (ll)MOD / i * invs[MOD % i] % MOD;
  for (int i = (1); i < (SZ); ++i) {
    fac[i] = (ll)fac[i - 1] * i % MOD;
    ifac[i] = (ll)ifac[i - 1] * invs[i] % MOD;
  }
}
mi comb(int a, int b) {
  if (a < b || b < 0) return 0;
  return (ll)fac[a] * ifac[b] % MOD * ifac[a - b] % MOD;
}
ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; }
ll lcm(ll a, ll b) { return (a / gcd(a, b)) * b; }
ll ncr(ll a, ll b) {
  if (a < b) return 0;
  ll f = 1;
  for (int i = (1); i < (b + 1); ++i) {
    f *= (a + 1 - i);
    f /= i;
  }
  return f;
}
void DBG() { cerr << "]" << endl; }
template <class T, class... U>
void DBG(const T& t, const U&... u) {
  cerr << to_string(t);
  if (sizeof...(u)) cerr << ", ";
  DBG(u...);
}
V<vi> reg(int n, int m) {
  V<vi> g(n);
  for (int i = (0); i < (m); ++i) {
    int a, b;
    re(a, b);
    a--;
    b--;
    g[a].push_back(b);
    g[b].push_back(a);
  }
  return g;
}
V<vpi> rew(int n, int m) {
  V<vpi> g(n);
  for (int i = (0); i < (m); ++i) {
    int a, b, w;
    re(a, b, w);
    a--;
    b--;
    g[a].emplace_back(b, w);
    g[b].emplace_back(a, w);
  }
  return g;
}
void setPrec() { cout << fixed << setprecision(15); }
void setIn(str s) { freopen(s.c_str(), "r", stdin); }
void setOut(str s) { freopen(s.c_str(), "w", stdout); }
void unsyncIO() { cin.tie(0)->sync_with_stdio(0); }
void setIO(str s = "") {
  unsyncIO();
  setPrec();
  if (((int)(s).size())) {
    setIn(s + ".in");
    setOut(s + ".out");
  }
}
const int N = 2e5 + 5;
void solve(int tc) {
  ll n;
  re(n);
  vpl v(n);
  re(v);
  ll x = 0;
  sort((v).begin(), (v).end(),
       [](pl& a, pl& b) { return a.first - a.second > b.first - b.second; });
  for (int i = (0); i < (n); ++i)
    x += (v[i].first * i) + (v[i].second * (n - i - 1));
  ps(x);
}
int main() {
  setIO();
  int T = 1;
  for (int _ = (1); _ < (T + 1); ++_) solve(_);
}
