Submission #442044

#	Time	Username	Problem	Language	Result	Execution time	Memory
442044		JovanB	Watching (JOI13_watching)	C++17	100 / 100	221 ms	16028 KiB

watching

#include <bits/stdc++.h>
using namespace std;
 
typedef long long ll;
typedef long double ld;
 
int n, p, q;
int event[2005];
int dp[2005][2005];
 
bool check(int w){
    int small = 0, large = 0;
    for(int i=1; i<=n; i++){
        while(event[i]-event[small+1] >= w) small++;
        while(event[i]-event[large+1] >= 2*w) large++;
        for(int j=0; j<=p; j++){
            dp[i][j] = n+5;
            if(j) dp[i][j] = min(dp[i][j], dp[small][j-1]);
            dp[i][j] = min(dp[i][j], dp[large][j] + 1);
        }
    }
    //if(w == 3) cout << dp[n][p] << " " << q << endl;
    return dp[n][p] <= q;
}
 
int main(){
    ios_base::sync_with_stdio(false), cin.tie(0);
    cout.precision(10);
    cout << fixed;
 
    cin >> n >> p >> q;
    p = min(p, n);
    q = min(q, n);
    for(int i=1; i<=n; i++){
        cin >> event[i];
    }
    sort(event+1, event+1+n);
    int l = 1, r = 1e9, res = 1e9;
    while(l <= r){
        int mid = (l+r)/2;
        if(check(mid)){
            r = mid-1;
            res = mid;
        }
        else l = mid+1;
    }
    cout << res;
    return 0;
}

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