Submission #1237360

#	Time	Username	Problem	Language	Result	Execution time	Memory
1237360		Gray	Text editor (CEOI24_editor)	C++20	45 / 100	4051 ms	1074144 KiB

Main

#pragma GCC optimize("Ofast,unroll-loops")
#include<bits/stdc++.h>

#define ll int
#define ff first
#define ss second
#define ln "\n"

using namespace std;
const ll INF = 2e9;

void solve(){
    ll n; cin >> n;
    ll sr, sc; cin >> sr >> sc;
    ll er, ec; cin >> er >> ec;
    vector<ll> a(n);
    for (ll i=0; i<n; i++){
        cin >> a[i]; a[i]++;
    }

    vector<array<ll, 5>> e;
    vector<ll> st;
    vector<vector<ll>> ptsc(n);
    vector<ll> con; 
    for (ll i=n-1; i>=0; i--){
        con.clear();
        con.push_back(1);
        con.push_back(a[i]);
        if (a[i]>=sc) con.push_back(sc);
        if (a[i]>=ec) con.push_back(ec);
        if (i+1<n) con.push_back(a[i+1]);
        if (i) con.push_back(a[i-1]);
        sort(con.begin(), con.end()); 
        con.erase(unique(con.begin(), con.end()), con.end());
        ptsc[i]=con;
        for (ll j=1; j<(ll)con.size(); j++){
            e.push_back({i+1, con[j-1], i+1, con[j], con[j]-con[j-1]});
            e.push_back({i+1, con[j], i+1, con[j-1],  con[j]-con[j-1]});
        }
        if (i){
            for (ll j=0; j<(ll)con.size(); j++){
                if (con[j]<=a[i-1]) {
                    e.push_back({i, con[j], i+1, con[j], 1});
                    e.push_back({i+1, con[j], i, con[j], 1});
                }
            }
            e.push_back({i, a[i-1], i+1, 1, 1});
            e.push_back({i+1, 1, i, a[i-1], 1});
        }
        if (i+1<n){
            for (ll j=0; j<(ll)con.size(); j++){
                if (con[j]<=a[i+1]) {
                    e.push_back({i+1, con[j], i+2, con[j], 1});
                    e.push_back({i+2, con[j], i+1, con[j], 1});
                }
            }
        }
        while(!st.empty() and a[st.back()]>=a[i]) st.pop_back();
        if (!st.empty()){
            ll lim=a[st.back()];
            for (ll j=con.size()-1; j>=0 and con[j]>lim; j--){
                e.push_back({i+1, con[j], st.back()+1, a[st.back()], st.back()-i});
            }
        }
        st.push_back(i);
    }
    st.clear();
    for (ll i=0; i<n; i++){
        while(!st.empty() and a[st.back()]>=a[i]) st.pop_back();
        if (!st.empty()){
            ll lim=a[st.back()];
            for (ll j=ptsc[i].size()-1; j>=0 and ptsc[i][j]>lim; j--){
                e.push_back({i+1, ptsc[i][j], st.back()+1, a[st.back()], i-st.back()});
            }
        }
        st.push_back(i);
    }
    vector<pair<ll, ll>> pts;
    pts.push_back({er, ec});
    pts.push_back({sr, sc});
    for (auto [fr, fc, tr, tc, w]:e){
        // cout << fr << " " << fc << " - " << tr << " " << tc << ": " << w << ln;
        pts.push_back({fr, fc});
        pts.push_back({tr, tc});
    }
    sort(pts.begin(), pts.end());
    pts.erase(unique(pts.begin(), pts.end()), pts.end());
    vector<vector<pair<ll, ll>>> A(pts.size());
    auto getid = [&](ll r, ll c){
        return lower_bound(pts.begin(), pts.end(), make_pair(r, c))-pts.begin();
    };
    for (auto [fr, fc, tr, tc, w]:e){
        assert(w>0);
        ll fid = getid(fr, fc), tid = getid(tr, tc);
        A[fid].push_back({tid, w});
    }

    priority_queue<pair<ll, ll>, vector<pair<ll, ll>>, greater<pair<ll, ll>>> que;
    vector<ll> dist(pts.size(), INF), vis(pts.size()); ll root=getid(sr, sc);
    que.push({0, root}); dist[root]=0;
    while (!que.empty()){
        auto cur = que.top(); que.pop();
        ll u = cur.ss, sw = cur.ff;
        if (vis[u]) continue;
        vis[u]=1;
        for (auto [v, w]:A[u]){
            if (dist[v]>w+sw){
                que.push({w+sw, v}); dist[v]=w+sw;
            }
        }
    }
    cout << dist[getid(er, ec)] << ln;
}

int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    ll t=1; 
    // cin >> t;
    while (t--){
        solve();
    }
}

• Subtask 0: 0 / 0
• Subtask 1: 5 / 5
• Subtask 2: 14 / 14
• Subtask 3: 26 / 26
• Subtask 4: 0 / 11
• Subtask 5: 0 / 44