Submission #535938

#	Time	Username	Problem	Language	Result	Execution time	Memory
535938		michao	Watching (JOI13_watching)	C++14	100 / 100	314 ms	31796 KiB

watching

#include <bits/stdc++.h>
#define int long long
#define mp make_pair
#define pb push_back
#define ld long double
#define pii pair<int,int>
#define sz(x) (int)x.size()
#define piii pair<pii,pii>
#define precise cout<<fixed<<setprecision(10)
#define st first
#define nd second
#define ins insert
#define vi vector<int>
#define BOOST ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0)
using namespace std;
const int MAX=2005;
const int inf=(int)1e9+9;
int a[MAX];
int dp[MAX][MAX];
int r1[MAX];
int r2[MAX];
int n,p,q;
bool check(int mid){
	for (int i=0;i<=n;i++)for (int j=0;j<=n;j++)dp[i][j]=0;
	for (int i=1;i<=n;i++){
		for (int j=1;j<=n;j++){
			if (a[j]-a[i]+1<=mid)r1[i]=j;
			if (a[j]-a[i]+1<=mid*2)r2[i]=j;
		}
	}
	for (int i=0;i<=p;i++){
		for (int j=0;j<=q;j++){
			if (dp[i][j]==n)return true;
			int l=dp[i][j]+1;
			if (i!=p)
			dp[i+1][j]=max(dp[i+1][j],r1[l]);
			if (j!=q)
			dp[i][j+1]=max(dp[i][j+1],r2[l]);
		}
	}
	return false;
}
int32_t main(){
  BOOST;
  cin>>n>>p>>q;
  p=min(p,n);
  q=min(q,n);
  for (int i=1;i<=n;i++)cin>>a[i];
  sort(a+1,a+n+1);
  int ip=0,ik=inf;
  while (ip+1<ik){
		int mid=(ip+ik)>>1;
		if (check(mid))ik=mid;
		else ip=mid;
  }
  cout<<ik;
  return 0; 
}

• Subtask 1: 50 / 50
• Subtask 2: 50 / 50