Submission #1012471

#	Time	Username	Problem	Language	Result	Execution time	Memory
1012471		Error404	Watching (JOI13_watching)	C++17	0 / 100	373 ms	262144 KiB

watching

#include "bits/stdc++.h"
using namespace std;
#define ll long long
#define f first
#define s second
#define vi vector<ll>
#define pb push_back
#define INF 100000000000
#define endl '\n'
#define int ll
int n,p,q;
vi v;

bool check(int k){
    int dp[p+1][q+1];
    memset(dp,0,sizeof(dp));
    ll where;
    //cout << "K: " << k <<endl; 
    for(int i = 0; i<= p; i++){
        for(int j =0 ; j<= q;j++){
            if(i==0 && j==0) dp[i][j] =1;
            else if(i==0){
                where = dp[i][j-1];
                
                dp[i][j] =  upper_bound(v.begin(), v.end(), v[where]+k*2-1) - v.begin();
              //  cout <<i << " " <<j << " " << dp[i][j]<<endl;
            }
            else if(j==0){
                 where = dp[i-1][j];
                dp[i][j] =  upper_bound(v.begin(), v.end(), v[where]+k-1) - v.begin();
               //   cout <<i << " " <<j << " " << dp[i][j]<<endl;
            }
            else {
                where = dp[i-1][j];
                dp[i][j] =  upper_bound(v.begin(), v.end(), v[where]+k-1) - v.begin();
                 where = dp[i][j-1];
                 int hold = (upper_bound(v.begin(), v.end(), v[where]+k*2-1) - v.begin());
                dp[i][j] =  max(dp[i][j],hold);
              //    cout <<i << " " <<j << " " << dp[i][j]<<endl;

            }
            if(dp[i][j]==n+1){
                return true;
            }
        }
    }
    return false;
}



signed main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

    cin >> n >> p >> q;
    ll l = 1, r= INT_MAX;

    v.resize(n+1);
    v[0]=-INF;
    for(int i =1; i <= n; i++){
        cin >> v[i];
    }
    sort(v.begin(),v.end());
    ll ans = 0;
    while(l<=r){
        int m = (l+r)/2;
       // cout <<"RES: " <<m << " "<<check(m)<<endl;
        if(check(m)){
            ans = m;
            r = m-1;
        }
        else l= m+1;
    }


    cout << ans << endl;

}

• Subtask 1: 0 / 50
• Subtask 2: 0 / 50