oj.uz

Submission #239721

# Submission time Handle Problem Language Result Execution time Memory
239721 2020-06-17T08:11:10 Z rajarshi_basu Watching (JOI13_watching) C++14
100 / 100
 873 ms 16248 KB 
//#pragma GCC optimize("Ofast")
//#pragma GCC target("avx,avx2,fma")

#include <stdio.h>     
#include <stdlib.h>    
#include <iostream>
#include <vector>
#include <algorithm>
#include <fstream>
#include <queue>
#include <deque>
#include <iomanip>
#include <cmath>
#include <set>
#include <stack>
#include <map>
#include <unordered_map>
 
#define FOR(i,n) for(int i=0;i<n;i++)
#define FORE(i,a,b) for(int i=a;i<=b;i++)
#define ll long long 
#define ld long double
#define vi vector<int>
#define pb push_back
#define ff first
#define ss second
#define il pair<int,ll>
#define ii pair<int,int>
#define lii pair<pair<ll,int>,il>
#define iii pair<int,ii>
#define iiii pair<iii,int>
#define pll pair<ll,ll>
#define plll pair<ll,pll>
#define vv vector
#define endl '\n'
 
using namespace std;

const int MAXN = 2e3+5;
const int INF = 1e8;

int arr[MAXN];
int n,p,q;
         
int dp[MAXN][MAXN];
bool check(int w){

    FOR(i,q)FOR(j,n)dp[i][j] = INF;
    FOR(i,q+1){
        int ptr1 = 0;
        int ptr2 = 0;
        FOR(j,n){
            while(arr[ptr1]+w-1 < arr[j])ptr1++;
            int prevInd = ptr1-1;
            if(prevInd == -1){
                dp[i][j] = 1;
            }else{
                dp[i][j] = dp[i][prevInd] + 1;
            }      

            // using a q here
            if(i > 0){
                while(arr[ptr2]+w*2-1<arr[j])ptr2++;
                prevInd = ptr2-1;
                if(prevInd == -1){
                    dp[i][j] = 0;
                }else{
                    dp[i][j] = min(dp[i][j],dp[i-1][prevInd]);
                }
            }                              
        }
    }
    
    return dp[q][n-1] <= p;
}


int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cin >> n >> p >> q;

    p = min(n,p);
    q = min(n,q);

    FOR(i,n)cin >> arr[i];
    sort(arr,arr+n);
    int lo = 1;
    int hi = 1e9;
    //cout << check(4) << endl;
    int ans = 1e9;
    while(lo <= hi){
        int mid = (lo+hi)/2;
        if(check(mid)){
            ans = min(ans,mid);
            hi = mid-1;
        }else{
            lo = mid+1;
        }
    }
    cout << ans << endl;

    return 0;
}

Subtask #1
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 384 KB Output is correct
2 Correct 4 ms 384 KB Output is correct
3 Correct 5 ms 384 KB Output is correct
4 Correct 5 ms 384 KB Output is correct
5 Correct 7 ms 768 KB Output is correct
6 Correct 7 ms 768 KB Output is correct
7 Correct 5 ms 384 KB Output is correct
8 Correct 5 ms 384 KB Output is correct
9 Correct 5 ms 384 KB Output is correct
10 Correct 7 ms 640 KB Output is correct
11 Correct 5 ms 384 KB Output is correct
12 Correct 6 ms 512 KB Output is correct
13 Correct 5 ms 384 KB Output is correct
14 Correct 5 ms 384 KB Output is correct
15 Correct 5 ms 384 KB Output is correct

Subtask #2
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 384 KB Output is correct
2 Correct 5 ms 384 KB Output is correct
3 Correct 605 ms 12280 KB Output is correct
4 Correct 37 ms 1024 KB Output is correct
5 Correct 826 ms 16248 KB Output is correct
6 Correct 873 ms 16120 KB Output is correct
7 Correct 11 ms 512 KB Output is correct
8 Correct 314 ms 6272 KB Output is correct
9 Correct 57 ms 1400 KB Output is correct
10 Correct 43 ms 1024 KB Output is correct
11 Correct 833 ms 15328 KB Output is correct
12 Correct 422 ms 8140 KB Output is correct
13 Correct 10 ms 512 KB Output is correct
14 Correct 8 ms 512 KB Output is correct
15 Correct 10 ms 512 KB Output is correct