Submission #417441

#	Time	Username	Problem	Language	Result	Execution time	Memory
417441		doowey	Autobahn (COI21_autobahn)	C++14	50 / 100	1097 ms	61520 KiB

autobahn

#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<int, int> pii;

#define fi first
#define se second
#define mp make_pair
#define fastIO ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);

const int N = (int)1e6 + 10;
int T[N];
int L[N];
int R[N];

vector<int> imp;
vector<pii> segm;
int cnt[N];
int ban[N];
struct Node{
    ll val;
    int cnt;
    ll lzy;
};

Node TR[N * 4 + 512];

void push(int node, int cl, int cr){
    TR[node].val += TR[node].lzy * 1ll * (segm[cr].se - segm[cl].fi + 1);
    TR[node].cnt += TR[node].lzy;
    if(cl != cr){
        TR[node * 2].lzy += TR[node].lzy;
        TR[node * 2 + 1].lzy += TR[node].lzy;
    }
    TR[node].lzy = 0;
}

void upd(int node, int cl, int cr, int tl, int tr, int v){
    push(node, cl, cr);
    if(cr < tl || cl > tr) return;
    if(cl >= tl && cr <= tr){
        TR[node].lzy = v;
        push(node, cl, cr);
        return;
    }
    int mid =(cl + cr) / 2;
    upd(node * 2, cl, mid, tl, tr, v);
    upd(node * 2 + 1, mid + 1, cr, tl, tr, v);
    TR[node].val = TR[node * 2].val + TR[node * 2 + 1].val;
}

int getcnt(int node, int cl, int cr, int iq){
    push(node, cl, cr);
    if(cl == cr)
        return TR[node].cnt;
    int mid = (cl + cr) / 2;
    if(mid >= iq)
        return getcnt(node * 2, cl, mid, iq);
    else
        return getcnt(node * 2 + 1, mid + 1, cr, iq);
}

ll get(int node, int cl, int cr, int tl, int tr){
    push(node, cl, cr);
    if(cr < tl || cl > tr) return 0ll;
    if(cl >= tl && cr <= tr){
        return TR[node].val;
    }
    int mid = (cl + cr) / 2;
    return get(node * 2, cl, mid, tl, tr) + get(node * 2 + 1, mid + 1, cr, tl, tr);
}


int main(){
    fastIO;
    int n, k, x;
    cin >> n >> k >> x;

    for(int i = 1; i <= n; i ++ ){
        cin >> L[i] >> T[i] >> R[i];
        imp.push_back(L[i]);
        imp.push_back(R[i]);
        if(L[i] + T[i] <= R[i]){
            imp.push_back(L[i] + T[i]);
        }
    }


    sort(imp.begin(), imp.end());
    imp.resize(unique(imp.begin(), imp.end()) - imp.begin());

    for(int i = 0 ; i < imp.size(); i ++ ){
        segm.push_back(mp(imp[i], imp[i]));
        if(i + 1 < imp.size()){
            if(imp[i] + 1 <= imp[i + 1] - 1)
                segm.push_back(mp(imp[i] + 1, imp[i + 1] - 1));
        }
    }
    int m = segm.size();
    int lf, rf;
    for(int i = 1; i <= n; i ++ ){
        lf = lower_bound(segm.begin(), segm.end(), mp(L[i], L[i])) - segm.begin();
        rf = lower_bound(segm.begin(), segm.end(), mp(R[i], R[i])) - segm.begin();
        cnt[lf] ++ ;
        cnt[rf + 1] -- ;
        if(L[i] + T[i] <= R[i]){
            lf = lower_bound(segm.begin(), segm.end(), mp(L[i] + T[i], L[i] + T[i])) - segm.begin();
            ban[lf] ++ ;
            ban[rf + 1] -- ;
        }
    }
    ll res = 0;
    for(int i = 1; i < m ; i ++ ){
        cnt[i] += cnt[i - 1];
        ban[i] += ban[i - 1];
    }
    for(int i = 0 ; i < m ; i ++ ){
        if(cnt[i] < k){
            ban[i] = 0;
        }
    }
    for(int i = 0 ; i < m ; i ++ ){
        upd(1, 0, m - 1, i, i, ban[i]);
    }
    int iqx;
    int nex;
    int las;
    ll val;
    int cc;
    for(int i = 0 ; i < m ; i ++ ){
        las = lower_bound(segm.begin(), segm.end(), mp(segm[i].fi + x, -1)) - segm.begin();
        if(las == m) las ++ ;
        las -- ;
        val = get(1, 0, m - 1, i, las - 1);
        if(las < m){
            cc = getcnt(1, 0, m - 1, las);
            val += max(0,((segm[i].fi + x - 1) - segm[las].fi + 1)) * 1ll * cc;
        }
        res = max(res, val);


        las = lower_bound(segm.begin(), segm.end(), mp(segm[i].se - x + 1, -1)) - segm.begin();
        val = get(1, 0, m - 1, las, i);
        if(las > 0){
            cc = getcnt(1, 0, m - 1, las - 1);
            val += max(0,(segm[las - 1].se - (segm[i].se - x + 1) + 1)) * 1ll * cc;
        }
        res = max(res, val);

    }

    cout << res << "\n";
    return 0;
}

Compilation message (stderr)

autobahn.cpp: In function 'int main()':
autobahn.cpp:94:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   94 |     for(int i = 0 ; i < imp.size(); i ++ ){
      |                     ~~^~~~~~~~~~~~
autobahn.cpp:96:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   96 |         if(i + 1 < imp.size()){
      |            ~~~~~~^~~~~~~~~~~~
autobahn.cpp:127:9: warning: unused variable 'iqx' [-Wunused-variable]
  127 |     int iqx;
      |         ^~~
autobahn.cpp:128:9: warning: unused variable 'nex' [-Wunused-variable]
  128 |     int nex;
      |         ^~~

• Subtask 1: 20 / 20
• Subtask 2: 30 / 30
• Subtask 3: 0 / 50