Submission #937097

#	Time	Username	Problem	Language	Result	Execution time	Memory
937097		Regulus	Sails (IOI07_sails)	C++17	100 / 100	73 ms	3928 KiB

sails

#include <bits/stdc++.h>
#define IO ios::sync_with_stdio(false);cin.tie(0);
#define debug(x) cerr << #x << " = " << (x) << ' '
#define bug(x) cerr << (x) << ' '
#define endl cerr << '\n'
#define all(v) (v).begin(), (v).end()
#define SZ(v) (ll)(v).size()
#define lowbit(x) (x)&-(x)
#define pb emplace_back
#define F first
#define S second
using namespace std;
using ll = long long;
using pll = pair<ll, ll>;
//#define TEST
const int N = 1e5+5;
ll bit[N];
pll a[N];

inline void upd(int x, int val)
{
    if (x <= 0) assert(0);
    for (int i=x; i <= 1e5; i+=lowbit(i)) bit[i] += val;
}
inline ll query(int x)
{
    ll ret = 0;
    for (int i=x; i > 0; i-=lowbit(i)) ret += bit[i];
    return ret;
}

inline ll banana_search(int lb, int ub, int mx)
{
    int mid;
    while (lb < ub)
    {
        mid = (lb + ub) >> 1;
        if (query(mid) <= mx) ub = mid;
        else lb = mid + 1;
    }
    return lb;
}

int main(void)
{ IO
    int n, i;
    
    cin >> n;
    for (i=1; i <= n; ++i) cin >> a[i].F >> a[i].S;

    sort(a+1, a+n+1);
    for (i=1; i <= n; ++i)
    {
        int mx = query(a[i].F-a[i].S+1);
        int it = banana_search(1, a[i].F+1, mx);
        int it2 = banana_search(1, a[i].F+1, mx-1);
        int cnt = it2 - (a[i].F-a[i].S+1);

        //debug(mx), debug(it), debug(it2), debug(cnt), endl;

        upd(it2, 1), upd(a[i].F+1, -1);
        upd(it, 1), upd(it+cnt, -1);
    }

    ll ans = 0;
    for (i=1; i <= 1e5; ++i)
    {
        ll tmp = query(i) - 1;
        if (tmp < -1) assert(0);
        ans += (tmp * (tmp + 1)) >> 1;
    }

    cout << ans << '\n';

    return 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 5 / 5
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 10 / 10
• Subtask 10: 10 / 10
• Subtask 11: 10 / 10