oj.uz

Submission #536657

# Submission time Handle Problem Language Result Execution time Memory
536657 2022-03-13T17:03:20 Z errorgorn Planine (COCI21_planine) C++17
110 / 110
 244 ms 46156 KB 
// Super Idol的笑容
//    都没你的甜
//  八月正午的阳光
//    都没你耀眼
//  热爱105°C的你
// 滴滴清纯的蒸馏水

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/rope>
using namespace std;
using namespace __gnu_pbds;
using namespace __gnu_cxx;
#define int long long
#define ll long long
#define ii pair<ll,ll>
#define iii pair<ii,ll>
#define fi first
#define se second
#define endl '\n'
#define debug(x) cout << #x << ": " << x << endl

#define pub push_back
#define pob pop_back
#define puf push_front
#define pof pop_front
#define lb lower_bound
#define ub upper_bound

#define rep(x,start,end) for(auto x=(start)-((start)>(end));x!=(end)-((start)>(end));((start)<(end)?x++:x--))
#define all(x) (x).begin(),(x).end()
#define sz(x) (int)(x).size()

#define indexed_set tree<ll,null_type,less<ll>,rb_tree_tag,tree_order_statistics_node_update>
//change less to less_equal for non distinct pbds, but erase will bug

mt19937 rng(chrono::system_clock::now().time_since_epoch().count());

int n,h;
ii arr[1000005];

double slope(int i,int j){
	return (double)(arr[j].fi-arr[i].fi)/(arr[j].se-arr[i].se);
}

double inter(int i,int j){
	return arr[i].fi-arr[i].se*slope(i,j);
}

double hval(int i,int j){
	return arr[i].fi+(h-arr[i].se)*slope(i,j);
}

vector<double> solve(){
	vector<double> res={1e100};
	
	vector<int> idx;
	
	rep(x,n,1){
		if (x%2==0){
			while (!idx.empty() && arr[x].se>=arr[idx.back()].se) idx.pob();
			while (sz(idx)>=2 && slope(x,idx.back())>=slope(idx.back(),idx[sz(idx)-2])) idx.pob();
			idx.pub(x);
		}
		else{
			double temp=1e100;
			for (auto it:idx) temp=min(temp,hval(x,it));
			res.pub(temp);
		}
	}
	
	reverse(all(res));
	return res;
}

signed main(){
	ios::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	cin.exceptions(ios::badbit | ios::failbit);
	
	cin>>n>>h;
	rep(x,1,n+1) cin>>arr[x].fi>>arr[x].se;
	
	auto temp=solve();
	reverse(arr+1,arr+n+1);
	rep(x,1,n+1) arr[x].fi=-arr[x].fi;
	auto temp2=solve();
	
	reverse(all(temp2));
	
	#define dd pair<double,double>
	vector<dd> ranges;
	
	rep(x,1,(n-1)/2) ranges.pub({-temp2[x],temp[x]});
	
	sort(all(ranges));
	double curr=-1e100;
	
	int ans=0;
	for (auto [l,r]:ranges){
		if (curr<l) curr=r,ans++;
		else curr=min(curr,r);
	}
	
	cout<<ans<<endl;
}

Subtask #1
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 724 KB Output is correct
2 Correct 3 ms 724 KB Output is correct
3 Correct 3 ms 724 KB Output is correct
4 Correct 19 ms 3804 KB Output is correct
5 Correct 25 ms 3804 KB Output is correct
6 Correct 22 ms 3788 KB Output is correct
7 Correct 176 ms 32080 KB Output is correct
8 Correct 205 ms 32180 KB Output is correct
9 Correct 218 ms 32160 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 340 KB Output is correct
2 Correct 1 ms 340 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 1 ms 340 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 1 ms 340 KB Output is correct
7 Correct 0 ms 340 KB Output is correct

Subtask #3
60.0 / 60.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 724 KB Output is correct
2 Correct 3 ms 724 KB Output is correct
3 Correct 3 ms 724 KB Output is correct
4 Correct 19 ms 3804 KB Output is correct
5 Correct 25 ms 3804 KB Output is correct
6 Correct 22 ms 3788 KB Output is correct
7 Correct 176 ms 32080 KB Output is correct
8 Correct 205 ms 32180 KB Output is correct
9 Correct 218 ms 32160 KB Output is correct
10 Correct 1 ms 340 KB Output is correct
11 Correct 1 ms 340 KB Output is correct
12 Correct 0 ms 212 KB Output is correct
13 Correct 1 ms 340 KB Output is correct
14 Correct 0 ms 212 KB Output is correct
15 Correct 1 ms 340 KB Output is correct
16 Correct 0 ms 340 KB Output is correct
17 Correct 240 ms 43216 KB Output is correct
18 Correct 220 ms 43048 KB Output is correct
19 Correct 30 ms 4916 KB Output is correct
20 Correct 230 ms 42252 KB Output is correct
21 Correct 21 ms 4820 KB Output is correct
22 Correct 225 ms 45896 KB Output is correct
23 Correct 1 ms 212 KB Output is correct
24 Correct 218 ms 45136 KB Output is correct
25 Correct 22 ms 4952 KB Output is correct
26 Correct 244 ms 46156 KB Output is correct
27 Correct 10 ms 2660 KB Output is correct