Submission #795221

#	Time	Username	Problem	Language	Result	Execution time	Memory
795221		raysh07	Watching (JOI13_watching)	C++17	100 / 100	541 ms	30364 KiB

watching

#include <bits/stdc++.h>
using namespace std;
#define int long long
#define INF (int)1e18
#define f first
#define s second

mt19937_64 RNG(chrono::steady_clock::now().time_since_epoch().count());

void Solve() 
{
    int n, p, q; cin >> n >> p >> q;
    
    vector <int> a(n);
    for (auto &x : a) cin >> x;
    sort(a.begin(), a.end());
    
    int l = 1, r = 1e9;
    
    if (p + q > n){
        cout << 1 <<  "\n";
        return;
    }
    
    while (r != l){
        int mid = (l + r)/2;
        
        vector<vector<int>> dp(n + 1, vector<int>(p + 1, INF));
        dp[0][0] = 0;
        
        for (int i = 1; i <= n; i++){
            int idx = lower_bound(a.begin(), a.end(), a[i - 1] + mid) - a.begin();
            int idx1 = lower_bound(a.begin(), a.end(), a[i - 1] + 2 * mid) - a.begin();
            
            for (int j = 0; j <= p; j++){
                if (j != p) dp[idx][j + 1] = min(dp[idx][j + 1], dp[i - 1][j]);
                
                dp[idx1][j] = min(dp[idx1][j], dp[i - 1][j] + 1);
            }
        }
        
        bool good = false;
        for (int j = 0; j <= p; j++){
            if (dp[n][j] <= q) good = true;
        }
        
        if (good) r = mid;
        else l = mid + 1;
    }
    
    cout << l << "\n";
}

int32_t main() 
{
    auto begin = std::chrono::high_resolution_clock::now();
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int t = 1;
   // cin >> t;
    for(int i = 1; i <= t; i++) 
    {
        //cout << "Case #" << i << ": ";
        Solve();
    }
    auto end = std::chrono::high_resolution_clock::now();
    auto elapsed = std::chrono::duration_cast<std::chrono::nanoseconds>(end - begin);
    cerr << "Time measured: " << elapsed.count() * 1e-9 << " seconds.\n"; 
    return 0;
}

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