Submission #950264

#	Time	Username	Problem	Language	Result	Execution time	Memory
950264		Tuanlinh123	Cake 3 (JOI19_cake3)	C++17	0 / 100	5 ms	17140 KiB

cake3

#include<bits/stdc++.h>
#define ll long long
#define pll pair<ll, ll>
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define ld long double
#define sz(a) ((ll)(a).size())
using namespace std;

const ll maxn=200005, inf=1e18;
ll n, m, v[maxn], c[maxn], p[maxn], lptr=1, rptr=0, ans=-inf;

namespace SegTree
{
    struct Node
    {
        ll cnt=0, sum=0;
        Node(){}
        Node(ll x): cnt(!!x), sum(x){}
    };
    Node St[maxn*4];

    void update(ll i, ll Start, ll End, ll idx, ll val)
    {
        if (Start>idx || End<idx) return;
        if (Start==End) {St[i]=Node(val); return;}
        ll mid=(Start+End)/2;
        if (mid>=idx) update(i*2, Start, mid, idx, val);
        else update(i*2+1, mid+1, End, idx, val);
        St[i].cnt=St[i*2].cnt+St[i*2+1].cnt;
        St[i].sum=St[i*2].sum+St[i*2+1].sum;
    }
    void update(ll idx, ll val){update(1, 1, n, idx, val);}

    ll query(ll i, ll Start, ll End, ll k)
    {
        if (Start==End)
        {
            if (!St[i].cnt) return -inf;
            return St[i].sum;
        }
        ll mid=(Start+End)/2;
        if (St[i*2+1].cnt>=k) return query(i*2+1, mid+1, End, k);
        return query(i*2, Start, mid, k-St[i*2+1].cnt)+St[i*2+1].sum;
    }
    ll query() {return query(1, 1, n, m);}
}

ll query(ll l, ll r)
{
    while (l<lptr) lptr--, SegTree::update(p[lptr], v[lptr]);
    while (r>rptr) rptr++, SegTree::update(p[rptr], v[rptr]);
    while (l>lptr) SegTree::update(p[lptr], 0), lptr++;
    while (r<rptr) SegTree::update(p[rptr], 0), rptr--;
    ll res=SegTree::query()-c[r]+c[l];
    ans=max(ans, res);
    return res;
}

void DnC(ll l, ll r, ll optl, ll optr)
{
    if (l>r) return;
    ll mid=(l+r)/2, res=0, opt=optl;
    for (ll i=optl; i<=optr && i<=mid-m+1; i++)
        tie(res, opt)=max(mp(res, opt), mp(query(i, mid), i));
    DnC(l, mid-1, optl, opt), DnC(mid+1, r, opt, optr);
}

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    cin >> n >> m;
    for (ll i=1; i<=n; i++)
        cin >> v[i] >> c[i], c[i]=c[i]*2;
    //sort
    {
        vector <pll> num;
        for (ll i=1; i<=n; i++) num.pb({c[i], v[i]});
        sort(num.begin(), num.end());
        for (ll i=0; i<sz(num); i++) tie(c[i+1], v[i+1])=num[i];
        num.clear();
        for (ll i=1; i<=n; i++) num.pb({v[i], i});
        sort(num.begin(), num.end());
        for (ll i=0; i<sz(num); i++) p[num[i].se]=i+1;
    }
    DnC(m, n, 1, n), cout << ans;
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 19
• Subtask 3: 0 / 76