Submission #1207550

#	Time	Username	Problem	Language	Result	Execution time	Memory
1207550		edga1	Watching (JOI13_watching)	C++20	100 / 100	110 ms	8520 KiB

watching

#include <bits/stdc++.h>

using namespace std;

long long a[2005];
int n,p,q;
int dp[2005][2005];

void check(int w){
    for(int i=0; i<=p; i++){
        for(int j=0; j<=q; j++){
            int pos,opos=dp[i][j]+1;
            if(i!=p){
                pos=dp[i][j]+1;
                while(pos<n-1){
                    if(a[pos+1]-a[opos]<w) pos++;
                    else break;
                }
                dp[i+1][j]=max(dp[i+1][j],min(pos,n-1));
            }
            if(j!=q){
                pos=dp[i][j]+1;
                while(pos<n-1){
                    if(a[pos+1]-a[opos]<w*2) pos++;
                    else break;
                }
                dp[i][j+1]=max(dp[i][j+1],min(pos,n-1));
            }
        }
    }
}

int bs(){
    int l=1,r=1e9+5,mid;
    while(l<=r){
        for(int i=0; i<=p; i++){
            for(int j=0; j<=q; j++){
                dp[i][j]=-1;
            }
        }
        mid=(l+r)/2;
        check(mid);
        if(dp[p][q]==n-1) r=mid-1;
        else l=mid+1;

    }
    return l;
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cin>>n>>p>>q;
    for(int i=0; i<n; i++) cin>>a[i];
    sort(a,a+n);
    if(p+q>=n){
        cout<<1;
        return 0;
    }
    cout<<bs();
    return 0;
}

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