Submission #472939

# Submission time Handle Problem Language Result Execution time Memory
472939 2021-09-14T15:27:02 Z Joo Watching (JOI13_watching) C++17
100 / 100
123 ms 15992 KB
#include <bits/stdc++.h>
#define DEBUG false
using namespace std;

const int N = 2e3+10;
int n,P,Q,dp[N][N];

main(){
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin >> n >> P >> Q;
    vector<int> a(n+1, 0);
    for(int i=1; i<=n; i++){
        cin >> a[i];
    }
    sort(a.begin(), a.end());
    if(P+Q >= n){
        cout << "1\n";
        return 0;
    }

    int l = 1, r = 1e9, ans = -1, lim = min(P, Q), chk = max(P, Q);
    int code = (P < Q);

    while(l <= r){
        int mid = (l+r)/2;
        for(int i=1, j1, j2; i<=n; i++){

            if(code == 0){
                j1 = lower_bound(a.begin()+1, a.end(), a[i]-2*mid+1)-a.begin();
                j2 = lower_bound(a.begin()+1, a.end(), a[i]-mid+1)-a.begin();
            }else{
                j1 = lower_bound(a.begin()+1, a.end(), a[i]-mid+1)-a.begin();
                j2 = lower_bound(a.begin()+1, a.end(), a[i]-2*mid+1)-a.begin();
            }

            for(int q=0; q<=lim; q++){
                dp[i][q] = 1e9;
                if(q > 0)
                    dp[i][q] = dp[j1-1][q-1];
                dp[i][q] = min(dp[i][q], dp[j2-1][q]+1);
            }
        }

        if(dp[n][lim] <= chk){
            ans = mid;
            r = mid-1;
        }else{
            l = mid+1;
        }
    }
    cout << ans << "\n";
}

Compilation message

watching.cpp:8:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
    8 | main(){
      | ^~~~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 716 KB Output is correct
2 Correct 0 ms 204 KB Output is correct
3 Correct 0 ms 332 KB Output is correct
4 Correct 0 ms 204 KB Output is correct
5 Correct 0 ms 204 KB Output is correct
6 Correct 1 ms 204 KB Output is correct
7 Correct 1 ms 716 KB Output is correct
8 Correct 1 ms 716 KB Output is correct
9 Correct 1 ms 716 KB Output is correct
10 Correct 1 ms 716 KB Output is correct
11 Correct 1 ms 716 KB Output is correct
12 Correct 1 ms 716 KB Output is correct
13 Correct 1 ms 716 KB Output is correct
14 Correct 1 ms 716 KB Output is correct
15 Correct 1 ms 716 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 7 ms 8364 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 1 ms 332 KB Output is correct
4 Correct 1 ms 332 KB Output is correct
5 Correct 1 ms 204 KB Output is correct
6 Correct 1 ms 204 KB Output is correct
7 Correct 9 ms 8460 KB Output is correct
8 Correct 21 ms 9292 KB Output is correct
9 Correct 22 ms 9320 KB Output is correct
10 Correct 22 ms 9040 KB Output is correct
11 Correct 18 ms 9044 KB Output is correct
12 Correct 123 ms 15992 KB Output is correct
13 Correct 9 ms 8396 KB Output is correct
14 Correct 10 ms 8464 KB Output is correct
15 Correct 11 ms 8396 KB Output is correct