Submission #758831

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
758831	2023-06-15T11:09:02 Z	Fidan	Watching (JOI13_watching)	C++17	50 / 100	1000 ms	31828 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){
	rep(i, 0, N){
		rep(j, 0, N){
			dp[i][j]=N;
		}
	}
	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){
			// x es el mas grande index tal que v[x]+w<=v[i]
			// y es el mas grande index tal que v[y]+2*w<=v[i]
			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);
		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	105 ms	31764 KB	Output is correct
2	Correct	16 ms	31768 KB	Output is correct
3	Correct	105 ms	31740 KB	Output is correct
4	Correct	15 ms	31700 KB	Output is correct
5	Correct	15 ms	31764 KB	Output is correct
6	Correct	15 ms	31752 KB	Output is correct
7	Correct	103 ms	31700 KB	Output is correct
8	Correct	105 ms	31740 KB	Output is correct
9	Correct	111 ms	31744 KB	Output is correct
10	Correct	105 ms	31744 KB	Output is correct
11	Correct	102 ms	31748 KB	Output is correct
12	Correct	105 ms	31700 KB	Output is correct
13	Correct	103 ms	31760 KB	Output is correct
14	Correct	108 ms	31792 KB	Output is correct
15	Correct	106 ms	31740 KB	Output is correct

Subtask #2

0 / 50.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	112 ms	31772 KB	Output is correct
2	Correct	15 ms	31644 KB	Output is correct
3	Correct	16 ms	31736 KB	Output is correct
4	Correct	15 ms	31776 KB	Output is correct
5	Correct	15 ms	31756 KB	Output is correct
6	Correct	16 ms	31828 KB	Output is correct
7	Correct	135 ms	31772 KB	Output is correct
8	Correct	243 ms	31772 KB	Output is correct
9	Correct	907 ms	31776 KB	Output is correct
10	Execution timed out	1084 ms	31700 KB	Time limit exceeded
11	Halted	0 ms	0 KB	-