Submission #758834

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
758834	2023-06-15T11:11:05 Z	Fidan	Watching (JOI13_watching)	C++17	50 / 100	1000 ms	31760 KB

watching

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define rep(i, a, b) for(ll i=ll(a); i<ll(b); i++)
#define repn(i, a, b) for(ll i=ll(b)-1; i>=ll(a); i--)
#define pb push_back
#define si size()
#define ff first
#define ss second
#define be begin()
#define en end()
const ll N=2002, P=2002;
vector<vector<ll>> dp(N, vector<ll> (P, N));
bool check(ll n, ll p, ll q, ll w, vector<ll> &v){
	dp[0][0]=1;
	rep(i, 1, p+1){
		dp[0][i]=0;
	}
	ll c=0;
	rep(i, 1, n){
		if(v[c]+2*w-1>=v[i]){
			dp[i][0]=dp[i-1][0];
		}
		else{
			c=i;
			dp[i][0]=dp[i-1][0]+1;
		}
	}
	rep(i, 1, n){
		rep(j, 1, p+1){
			dp[i][j]=N;
			if(v[0]+w>v[i]){
				dp[i][j]=0;
			}
			else{
				ll lo=0, hi=i-1;
				while(lo<hi){
					ll mid=(lo+hi+1)/2;
					if(v[mid]+w<=v[i]){
						lo=mid;
					}
					else{
						hi=mid-1;
					}
				}
				dp[i][j]=min(dp[i][j], dp[lo][j-1]);
			}
			if(v[0]+2*w>v[i]){
				dp[i][j]=min(dp[i][j], ll(1));
			}
			else{
				ll lo=0, hi=i-1;
				while(lo<hi){
					ll mid=(lo+hi+1)/2;
					if(v[mid]+2*w<=v[i]){
						lo=mid;
					}
					else{
						hi=mid-1;
					}
				}
				dp[i][j]=min(dp[i][j], dp[lo][j]+1);
			}
		}
	}
	if(dp[n-1][p]<=q){
		return true;
	}
	return false;
}
void solve(){
	ll n, p, q;
	cin>>n>>p>>q;
	vector<ll> v(n);
	rep(i, 0, n){
		cin>>v[i];
	}
	sort(v.be, v.en);
	if(p+q>=n){
		cout<<1;
	}
	else{
		ll lo=1, hi=(1e9)/3+2;
		while(lo<hi){
			ll mid=(lo+hi)/2;
			bool f=check(n, p, q, mid, v);
			if(f) hi=mid;
			else lo=mid+1;
		}
		cout<<hi;
	}
}
int main(){
	ios_base::sync_with_stdio();
	cin.tie(0);
	ll t=1;
	//~ cin>>t;
	while(t--){
		solve();
	}
	return 0;
}

Subtask #1

50.0 / 50.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	15 ms	31696 KB	Output is correct
2	Correct	17 ms	31700 KB	Output is correct
3	Correct	15 ms	31700 KB	Output is correct
4	Correct	17 ms	31716 KB	Output is correct
5	Correct	15 ms	31644 KB	Output is correct
6	Correct	15 ms	31664 KB	Output is correct
7	Correct	15 ms	31700 KB	Output is correct
8	Correct	15 ms	31712 KB	Output is correct
9	Correct	15 ms	31700 KB	Output is correct
10	Correct	16 ms	31636 KB	Output is correct
11	Correct	17 ms	31700 KB	Output is correct
12	Correct	19 ms	31640 KB	Output is correct
13	Correct	15 ms	31700 KB	Output is correct
14	Correct	15 ms	31640 KB	Output is correct
15	Correct	15 ms	31700 KB	Output is correct

Subtask #2

0 / 50.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	18 ms	31700 KB	Output is correct
2	Correct	15 ms	31700 KB	Output is correct
3	Correct	16 ms	31680 KB	Output is correct
4	Correct	16 ms	31700 KB	Output is correct
5	Correct	16 ms	31700 KB	Output is correct
6	Correct	16 ms	31700 KB	Output is correct
7	Correct	50 ms	31752 KB	Output is correct
8	Correct	153 ms	31748 KB	Output is correct
9	Correct	803 ms	31760 KB	Output is correct
10	Execution timed out	1079 ms	31700 KB	Time limit exceeded
11	Halted	0 ms	0 KB	-