oj.uz

Submission #289986

# Submission time Handle Problem Language Result Execution time Memory
289986 2020-09-03T09:37:08 Z BeanZ Watching (JOI13_watching) C++14
50 / 100
 1000 ms 20344 KB 
#include <bits/stdc++.h>

using namespace std;

#define ll long long
#define endl '\n'
const int N = 5e5 + 5;
ll n, p, q;
ll dp[2005][2005], a[2005];
bool chk(ll k){
        for (int i = 1; i <= n; i++){
                for (int j = 0; j <= q; j++){
                        dp[i][j] = 1e18;
                        ll l = 1, h = i;
                        ll w2 = a[i] - 2 * k + 1;
                        while (l <= h){
                                ll mid = (l + h) >> 1;
                                if (a[mid] < w2) l = mid + 1;
                                else h = mid - 1;
                        }
                        if (j > 0) dp[i][j] = min(dp[i][j], dp[l - 1][j - 1]);
                        l = 1, h = i;
                        ll w = a[i] - k + 1;
                        while (l <= h){
                                ll mid = (l + h) >> 1;
                                if (a[mid] < w) l = mid + 1;
                                else h = mid - 1;
                        }
                        dp[i][j] = min(dp[i][j], dp[l - 1][j] + 1);
                }
        }
        for (int i = 0; i <= q; i++){
                if (dp[n][i] <= p) return 1;
        }
        return 0;
}
int main(){
        ios_base::sync_with_stdio(false);
        cin.tie(0);
        if (fopen("simplify.in", "r")){
                freopen("simplify.in", "r", stdin);
                freopen("simplify.out", "w", stdout);
        }
        cin >> n >> p >> q;
        for (int i = 1; i <= n; i++) cin >> a[i];
        sort(a + 1, a + n + 1);
        if ((p + q) >= n) return cout << 1, 0;
        ll l = 1, h = 1e9;
        while (l <= h){
                ll mid = (l + h) >> 1;
                if (chk(mid)) h = mid - 1;
                else l = mid + 1;
        }
        cout << l;
}
/*
*/

Compilation message

watching.cpp: In function 'int main()':
watching.cpp:41:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   41 |                 freopen("simplify.in", "r", stdin);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
watching.cpp:42:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   42 |                 freopen("simplify.out", "w", stdout);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 768 KB Output is correct
2 Correct 1 ms 512 KB Output is correct
3 Correct 1 ms 384 KB Output is correct
4 Correct 0 ms 384 KB Output is correct
5 Correct 0 ms 384 KB Output is correct
6 Correct 0 ms 384 KB Output is correct
7 Correct 1 ms 768 KB Output is correct
8 Correct 1 ms 768 KB Output is correct
9 Correct 1 ms 768 KB Output is correct
10 Correct 3 ms 768 KB Output is correct
11 Correct 2 ms 768 KB Output is correct
12 Correct 3 ms 768 KB Output is correct
13 Correct 1 ms 768 KB Output is correct
14 Correct 1 ms 768 KB Output is correct
15 Correct 1 ms 768 KB Output is correct

Subtask #2
0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 8448 KB Output is correct
2 Correct 0 ms 384 KB Output is correct
3 Correct 1 ms 384 KB Output is correct
4 Correct 1 ms 384 KB Output is correct
5 Correct 1 ms 384 KB Output is correct
6 Correct 1 ms 384 KB Output is correct
7 Correct 36 ms 8576 KB Output is correct
8 Execution timed out 1006 ms 20344 KB Time limit exceeded
9 Halted 0 ms 0 KB -