Submission #954201

#	Time	Username	Problem	Language	Result	Execution time	Memory
954201		irmuun	Watching (JOI13_watching)	C++17	100 / 100	625 ms	31936 KiB

watching

#include<bits/stdc++.h>

using namespace std;

#define ll long long
#define pb push_back
#define ff first
#define ss second
#define all(s) s.begin(),s.end()
#define rall(s) s.rbegin(),s.rend()

int main(){
    ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    ll n,p,q;
    cin>>n>>p>>q;
    ll a[n+5];
    for(ll i=1;i<=n;i++){
        cin>>a[i];
    }
    if(p+q>=n){
        cout<<1;
        return 0;
    }
    sort(a+1,a+n+1);
    ll l=1,r=1e9;
    ll dp[n+5][n+5];
    while(l<r){
        ll w=(l+r)/2;
        memset(dp,0,sizeof dp);
        for(ll sum=0;sum<=p+q;sum++){
            for(ll i=0;i<=sum;i++){
                if(i<=p&&sum-i<=q){
                    ll j=sum-i;
                    if(i==0&&j==0){
                        dp[i][j]=0;
                        continue;
                    }
                    ll nxt=0;
                    if(i>0){
                        if(dp[i-1][j]==n){
                            dp[i][j]=n;
                            continue;
                        }
                        ll R=dp[i-1][j]+1;
                        R=lower_bound(a+1,a+n+1,a[dp[i-1][j]+1]+w)-a;
                        R--;
                        dp[i][j]=max(dp[i][j],R);
                    }
                    if(j>0){
                        if(dp[i][j-1]==n){
                            dp[i][j]=n;
                            continue;
                        }
                        ll R=dp[i][j-1]+1;
                        R=lower_bound(a+1,a+n+1,a[dp[i][j-1]+1]+2*w)-a;
                        R--;
                        dp[i][j]=max(dp[i][j],R);
                    }
                }
            }
        }
        if(dp[p][q]==n){
            r=w;
        }
        else{
            l=w+1;
        }
    }
    cout<<l;
}

Compilation message (stderr)

watching.cpp: In function 'int main()':
watching.cpp:38:24: warning: unused variable 'nxt' [-Wunused-variable]
   38 |                     ll nxt=0;
      |                        ^~~

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