oj.uz

Submission #471006

# Submission time Handle Problem Language Result Execution time Memory
471006 2021-09-06T15:34:13 Z iulia13 Watching (JOI13_watching) C++14
100 / 100
 287 ms 16012 KB 
#include <bits/stdc++.h>

using namespace std;
const int N = 2e3 + 5;
int n, p, q;
int a[N];
int dp[N][N];
int check(int val)
{
    int i1 = 0, i2 = 0, i, j;
    for (i = 0; i <= n; i++)
        for (j = 0; j <= p; j++)
            dp[i][j] = q + 1;
    dp[0][0] = 0;
    for (i = 1; i <= n; i++)
    {
        while (a[i1 + 1] + val <= a[i])
            i1++;
        while (a[i2 + 1] + val * 2 <= a[i])
            i2++;
        for (j = 0; j <= p; j++)
        {
            if (j)
                dp[i][j] = min(dp[i][j], dp[i1][j - 1]);
            dp[i][j] = min(dp[i][j], dp[i2][j] + 1);
        }
    }
    for (i = 0; i <= p; i++)
        if (dp[n][i] <= q)
            return 1;
    return 0;
}
int main()
{
    int i, sol;
    cin >> n >> p >> q;
    p = min(p, n);
    q = min(q, n);
    for (i = 1; i <= n; i++)
        cin >> a[i];
    sort(a + 1, a + n + 1);
    int st = 1, dr = 1e9;
    while (st <= dr)
    {
        int mid = (st + dr) / 2;
        if (check(mid))
        {
            sol = mid;
            dr = mid - 1;
        }
        else
            st = mid + 1;
    }
    cout << sol;
    return 0;
}

Compilation message

watching.cpp: In function 'int main()':
watching.cpp:54:13: warning: 'sol' may be used uninitialized in this function [-Wmaybe-uninitialized]
   54 |     cout << sol;
      |             ^~~

Subtask #1
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 588 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 1 ms 332 KB Output is correct
4 Correct 2 ms 716 KB Output is correct
5 Correct 1 ms 588 KB Output is correct
6 Correct 2 ms 716 KB Output is correct
7 Correct 1 ms 684 KB Output is correct
8 Correct 1 ms 588 KB Output is correct
9 Correct 1 ms 588 KB Output is correct
10 Correct 1 ms 588 KB Output is correct
11 Correct 1 ms 716 KB Output is correct
12 Correct 2 ms 716 KB Output is correct
13 Correct 1 ms 716 KB Output is correct
14 Correct 1 ms 588 KB Output is correct
15 Correct 1 ms 588 KB Output is correct

Subtask #2
50.0 / 50.0

# 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 228 ms 16012 KB Output is correct
4 Correct 271 ms 16004 KB Output is correct
5 Correct 23 ms 8952 KB Output is correct
6 Correct 280 ms 15948 KB Output is correct
7 Correct 9 ms 8396 KB Output is correct
8 Correct 27 ms 9272 KB Output is correct
9 Correct 124 ms 14156 KB Output is correct
10 Correct 287 ms 15948 KB Output is correct
11 Correct 22 ms 9036 KB Output is correct
12 Correct 166 ms 15996 KB Output is correct
13 Correct 9 ms 8444 KB Output is correct
14 Correct 10 ms 8484 KB Output is correct
15 Correct 10 ms 8372 KB Output is correct