oj.uz

Submission #988642

# Submission time Handle Problem Language Result Execution time Memory
988642 2024-05-25T11:05:27 Z parlimoos Building Bridges (CEOI17_building) C++17
100 / 100
 461 ms 13392 KB 
//Be Name KHODA
#pragma GCC optimize("Ofast")
#include<bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef long double ld;
#define pb push_back
#define pp pop_back
#define lb lower_bound
#define ub upper_bound
#define cl clear
#define bg begin
#define arr(x) array<ll , x>
#define endl '\n'

int n;
vector<ll> w , h;
ll dp[200000] , inf[200000][2];
set<arr(2)> pt;

void init(){
    for(int i = 1 ; i < n ; i++) w[i] += w[i - 1];
    for(int i = 0 ; i < n ; i++){
        inf[i][1] = (h[i] * h[i]) , inf[i][0] = (h[i] * h[i]) - w[i];
        if(i > 0) inf[i][1] += w[i - 1];
    }
}
bool jg(ll c , int i , int j){
    return (dp[i] - (2 * c * h[i]) <= dp[j] - (2 * c * h[j]));
}
int bsMx(int i){
    int l = 0 , r = int(1e6) + 1;
    while(r - l - 1 > 1){
        int c = (r + l + 1) >> 1;
        int inx = (*(--pt.ub({c , int(1e9)})))[1];
        if(h[inx] < h[i]) l = c - 1;
        else if(jg(c , i , inx)) l = c - 1;
        else r = c;
    }
    if(r - l - 1 == 1){
        int inx = (*(--pt.ub({l + 1 , int(1e9)})))[1];
        if(h[inx] < h[i]) return l + 1;
        else if(jg(l + 1 , i , inx)) return l + 1;
    }
    return l;
}
int bsMn(int i , int r){
    int l = -1;
    while(r - l - 1 > 1){
        int c = (r + l + 1) >> 1;
        int inx = (*(--pt.ub({c , int(1e9)})))[1];
        if(jg(c , i , inx)) r = c;
        else l = c - 1;
    }
    if(r - l - 1 == 1){
        int inx = (*(--pt.ub({r - 1 , int(1e9)})))[1];
        if(jg(r - 1 , i , inx)) return r - 1;
    }
    return r;
}
void addEl(int i){
    if(pt.empty()){
        pt.insert({0 , i});
        return;
    }
    int r = bsMx(i);
    int l = bsMn(i , r + 1);
    if(l > r) return;
    auto itr1 = pt.lb({l , -1}) , itr2 = pt.ub({r , int(1e9)});
    if(itr1 == itr2){
        pt.insert({l , i});
        return;
    }
    vector<arr(2)> dls , adds;
    itr2--;
    while(true){
        dls.pb((*itr1));
        if(itr2 == itr1){
            adds.pb({r + 1 , (*itr2)[1]});
            if((*++itr1)[0] == r + 1) adds.cl();
            break;
        }
        itr1++;
    }
    pt.insert({l , i});
    for(auto &el : dls) pt.erase(el);
    for(auto &el : adds) pt.insert(el);
}

int main(){
    ios::sync_with_stdio(0);
    cin.tie(0);

    cin >> n;
    for(int i = 0 ; i < n ; i++){
        h.pb(0);
        cin >> h.back();
    }
    for(int i = 0 ; i < n ; i++){
        w.pb(0);
        cin >> w.back();
    }
    init();
    dp[n - 1] += inf[n - 1][1];
    addEl(n - 1);
    for(int i = n - 2 ; i >= 0 ; i--){
        // for(auto el : pt) cout << el[0] << " " << el[1] << ",,\n";
        // cout << "-----\n";
        int inx = (*(--pt.ub({h[i] , int(1e9)})))[1];
        dp[i] = dp[inx] + inf[i][0] - (2 * h[i] * h[inx]);
        if(i > 0) dp[i] += inf[i][1];
        // cout << dp[i] << "!!\n";
        addEl(i);
    }
    // cout << jg(5 , 2 , 3) << "::\n";
    cout << dp[0] << "\n";
}

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2396 KB Output is correct
2 Correct 1 ms 2396 KB Output is correct
3 Correct 2 ms 2396 KB Output is correct
4 Correct 2 ms 2648 KB Output is correct
5 Correct 2 ms 2556 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 324 ms 6424 KB Output is correct
2 Correct 302 ms 6428 KB Output is correct
3 Correct 302 ms 6424 KB Output is correct
4 Correct 253 ms 6232 KB Output is correct
5 Correct 279 ms 8044 KB Output is correct

Subtask #3
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2396 KB Output is correct
2 Correct 1 ms 2396 KB Output is correct
3 Correct 2 ms 2396 KB Output is correct
4 Correct 2 ms 2648 KB Output is correct
5 Correct 2 ms 2556 KB Output is correct
6 Correct 324 ms 6424 KB Output is correct
7 Correct 302 ms 6428 KB Output is correct
8 Correct 302 ms 6424 KB Output is correct
9 Correct 253 ms 6232 KB Output is correct
10 Correct 279 ms 8044 KB Output is correct
11 Correct 248 ms 6428 KB Output is correct
12 Correct 302 ms 6372 KB Output is correct
13 Correct 116 ms 6232 KB Output is correct
14 Correct 292 ms 7516 KB Output is correct
15 Correct 461 ms 13392 KB Output is correct
16 Correct 307 ms 8932 KB Output is correct
17 Correct 32 ms 7504 KB Output is correct
18 Correct 34 ms 7764 KB Output is correct