| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 299788 | HynDuf | Sails (IOI07_sails) | C++11 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
#define task "S"
#define all(v) (v).begin(), (v).end()
#define rep(i, l, r) for (ll i = (l); i <= (r); ++i)
#define Rep(i, r, l) for (ll i = (r); i >= (l); --i)
#define DB(X) { cerr << #X << " = " << (X) << '\n'; }
#define DB1(A, _) { cerr << #A << "[" << _ << "] = " << (A[_]) << '\n'; }
#define DB2(A, _, __) { cerr << #A << "[" << _ << "][" << __ << "] = " << (A[_][__]) << '\n'; }
#define DB3(A, _, __, ___) { cerr << #A << "[" << _ << "][" << __ << "][" << ___ << "] = " << (A[_][__][___]) << '\n'; }
#define PR(A, l, r) { cerr << '\n'; rep(_, l, r) DB1(A, _); cerr << '\n';}
#define SZ(x) ((ll)(x).size())
#define pb push_back
#define eb emplace_back
#define pf push_front
#define F first
#define S second
#define by(x) [](const auto& a, const auto& b) { return a.x < b.x; } // sort(arr, arr + N, by(a));
#define next ___next
#define prev ___prev
#define y1 ___y1
#define left ___left
#define right ___right
#define y0 ___y0
#define div ___div
#define j0 ___j0
#define jn ___jn
using ll = long long;
using ld = long double;
using ull = unsigned long long;
using namespace std;
typedef pair<ll, ll> ii;
typedef pair<ii, ll> iii;
typedef vector<ll> vi;
typedef vector<ii> vii;
typedef vector<ll> vl;
const ll N = 1e5 + 2;
ll n, nn, cnt[N];
ii h[N];
ll ans = 0;
struct IT
{
vi it, lz;
IT(ll n) {it.assign(4 * n, 0); lz.assign(4 * n, 0);}
void dolazy(ll id, ll l, ll r)
{
if (!lz[id]) return;
it[id] += lz[id];
if (l != r)
{
lz[id << 1] += lz[id];
lz[(id << 1) | 1] += lz[id];
}
lz[id] = 0;
}
void update(ll id, ll l, ll r, ll L, ll R, ll v)
{
dolazy(id, l, r);
if (l > R || r < L || L > R) return;
if (L <= l && r <= R)
{
lz[id] += v;
dolazy(id, l, r);
return;
}
ll m = (l + r) >> 1;
update(id << 1, l, m, L, R, v);
update((id << 1) | 1, m + 1, r, L, R, v);
it[id] = min(it[id << 1], it[(id << 1) | 1]);
}
ll lastOccur(ll id, ll l, ll r, ll x)
{
dolazy(id, l, r);
if (l == r)
{
assert(it[id] == x);
return l;
}
ll m = (l + r) >> 1;
dolazy((id << 1) | 1, m + 1, r);
if (it[(id << 1) | 1] <= x) return lastOccur((id << 1) | 1, m + 1, r, x);
return lastOccur(id << 1, l, m, x);
}
};
int main()
{
#ifdef HynDuf
freopen(task".in", "r", stdin);
//freopen(task".out", "w", stdout);
#else
ios_base::sync_with_stdio(false); cin.tie(nullptr);
#endif
cin >> n;
rep(i, 1, n) cin >> h[i].F >> h[i].S, nn = max(nn, h[i].F);
sort(h + 1, h + 1 + n, greater<ii> ());
IT seg(nn);
rep(i, 1, n)
{
ll x = seg.it[1];
ll lO = seg.lastOccur(1, 1, nn, x);
assert(lO <= h[i].F);
seg.update(1, 1, nn, max(1, lO - h[i].S + 1), lO, 1);
cnt[max(1, lO - h[i].S + 1)]++;
cnt[lO + 1]--;
if (h[i].S > lO)
{
seg.update(1, 1, nn, h[i].F - (h[i].S - lO) + 1, h[i].F, 1);
cnt[h[i].F - (h[i].S - lO) + 1]++;
cnt[h[i].F + 1]--;
}
if (i < n) seg.update(1, 1, nn, h[i + 1].F + 1, h[i].F, N);
}
rep(i, 2, nn) cnt[i] += cnt[i - 1];
rep(i, 1, nn) ans += cnt[i] * 1LL * (cnt[i] - 1) / 2;
cout << ans;
return 0;
}