oj.uz

Submission #289984

# Submission time Handle Problem Language Result Execution time Memory
289984 2020-09-03T09:36:34 Z BeanZ Watching (JOI13_watching) C++14
50 / 100
 1000 ms 31988 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){
        memset(dp, 0, sizeof(dp));
        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: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.in", "r", stdin);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
watching.cpp:43:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   43 |                 freopen("simplify.out", "w", stdout);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 131 ms 31988 KB Output is correct
2 Correct 0 ms 384 KB Output is correct
3 Correct 133 ms 31872 KB Output is correct
4 Correct 1 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 131 ms 31856 KB Output is correct
8 Correct 129 ms 31744 KB Output is correct
9 Correct 132 ms 31744 KB Output is correct
10 Correct 130 ms 31744 KB Output is correct
11 Correct 139 ms 31744 KB Output is correct
12 Correct 132 ms 31744 KB Output is correct
13 Correct 136 ms 31744 KB Output is correct
14 Correct 125 ms 31744 KB Output is correct
15 Correct 129 ms 31856 KB Output is correct

Subtask #2
0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 140 ms 31872 KB Output is correct
2 Correct 1 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 164 ms 31872 KB Output is correct
8 Execution timed out 1082 ms 31872 KB Time limit exceeded
9 Halted 0 ms 0 KB -