Submission #999406

#	Time	Username	Problem	Language	Result	Execution time	Memory
999406		snpmrnhlol	Constellation 3 (JOI20_constellation3)	C++17	35 / 100	1565 ms	61268 KiB

constellation3

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const ll N = 2e5;
const ll G = 2*N;
ll n,m;
vector <ll> e[G];
ll v[N];
ll leftid[N],rightid[N];
ll leftside[N + 1],rightside[N + 1];
///
ll stk[N];
vector <ll> p;
struct star{
    ll x,y,c;
}v2[N];
vector <ll> cand[G];
map<ll,pair<ll,ll>> f;
vector <ll> polls;
ll dp[G];
ll cnt = 0;
void addedge(ll u,ll w){
    e[u].push_back(w);
}
void dfs(ll node){
    ll mx = 0;
    for(auto i:e[node]){
        dfs(i);
        mx+=dp[i];
    }
    for(auto i:cand[node]){
        ///leftadd
        star s = v2[i];
        ll candcost = s.c;
        for(ll j = s.x;j != n && v[j] < s.y;j = rightside[j]){
            if(rightid[j] != -1){candcost+=dp[rightid[j]];};
        }
        for(ll j = s.x;j != n && v[j] < s.y;j = leftside[j]){
            if(leftid[j] != -1){candcost+=dp[leftid[j]];};
        }
        mx = max(mx,candcost);
    }
    dp[node] = mx;
}
int main(){
    cin>>n;
    p.resize(n);
    for(ll i = 0;i < n;i++){
        cin>>v[i];
        p[i] = i;
        leftid[i] = rightid[i] = -1;
    }
    sort(p.begin(),p.end(),[&](ll a,ll b){
        if(v[a] == v[b])return a < b;
        return v[a] > v[b];
    });
    cin>>m;
    ll sum = 0;
    for(ll i = 0;i < m;i++){
        cin>>v2[i].x>>v2[i].y>>v2[i].c;
        sum+=v2[i].c;
        v2[i].x--;
    }
    sort(v2,v2 + m,[&](star a,star b){
         return a.y > b.y;
    });
    f[0] = {n - 1,cnt++};
    ll pt = 0;
    ll pt2 = 0;
    for(ll i = n;i >= 1;i--){
        polls.clear();
        while(pt2 < n && v[p[pt2]] >= i){
            polls.push_back(p[pt2]);
            pt2++;
        }
        ll j = 0;
        while(j < polls.size()){
            auto it = prev(f.upper_bound(polls[j]));
            ll k = j;
            while(k < polls.size() && polls[k] <= it->second.first){
                k++;
            }
            ll l = it->first;
            ll r = it->second.first;
            ll id = it->second.second;
            f.erase(it);
            for(ll p = j;p <= k;p++){
                ll lside = (p == j?l:polls[p - 1] + 1);
                ll rside = (p == k?r:polls[p] - 1);
                if(lside <= rside){
                    addedge(id,cnt);
                    f[lside] = {rside,cnt};
                    if(p != k){
                        leftid[rside + 1] = cnt;
                    }
                    if(p != j){
                        rightid[lside - 1] = cnt;
                    }
                    cnt++;
                }
            }
            j = k;
        }
        while(pt < m && v2[pt].y >= i){
            ll id = prev(f.upper_bound(v2[pt].x))->second.second;
            cand[id].push_back(pt);
            pt++;
        }
    }
    ll cnt2 = 0;
    for(ll i = 0;i < n;i++){
        while(cnt2 > 0 && v[i] > v[stk[cnt2 - 1]]){
            cnt2--;
        }
        leftside[i] = (cnt2 == 0?n:stk[cnt2 - 1]);
        stk[cnt2++] = i;
    }
    cnt2 = 0;
    for(ll i = n - 1;i >= 0;i--){
        while(cnt2 > 0 && v[i] > v[stk[cnt2 - 1]]){
            cnt2--;
        }
        rightside[i] = (cnt2 == 0?n:stk[cnt2 - 1]);
        stk[cnt2++] = i;
    }
    dfs(0);
    cout<<sum - dp[0];
    return 0;
}

Compilation message (stderr)

constellation3.cpp: In function 'int main()':
constellation3.cpp:77:17: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   77 |         while(j < polls.size()){
      |               ~~^~~~~~~~~~~~~~
constellation3.cpp:80:21: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   80 |             while(k < polls.size() && polls[k] <= it->second.first){
      |                   ~~^~~~~~~~~~~~~~

• Subtask 1: 14 / 14
• Subtask 2: 21 / 21
• Subtask 3: 0 / 65