oj.uz

Submission #56517

# Submission time Handle Problem Language Result Execution time Memory
56517 2018-07-11T14:45:30 Z luciocf Watching (JOI13_watching) C++14
0 / 100
 1000 ms 12628 KB 
#include <bits/stdc++.h>

using namespace std;

const int MAXN = 2010;

int n, p, q, num[MAXN];
int dp[MAXN][MAXN];

int busca2(int k)
{
    if (k > num[n]) return n;

    int ini = 1, fim = n, ans;
    while (ini <= fim)
    {
        int mid = (ini+fim)>>1;

        if (num[mid] <= k) ans = mid, ini = mid+1;
        else fim = mid-1;
    }
    return ans;
}

bool ok(int w)
{
    for (int i = 1; i <= p; i++)
        for (int j = 1; j <= q; j++)
            dp[i][j] = 1;

    for (int i = 0; i <= p; i++) dp[i][0] = 0;
    for (int j = 0; j <= q; j++) dp[0][j] = 0;

    for (int i = 0; i <= p; i++)
    {
        for (int j = 0; j <= q; j++)
        {
            if (!i && !j) continue;

            if (i)
                dp[i][j] = busca2(num[dp[i-1][j]+1]+w-1);
            if (j)
                dp[i][j] = max(dp[i][j], busca2(num[dp[i][j-1]+1]+2*w-1));
        }
    }
    return (dp[p][q] >= n);
}

int busca(void)
{
    int ini = 1, fim = 1e9, ans;
    while (ini <= fim)
    {
        int mid = (ini+fim)>>1;

        if (ok(mid)) ans = mid, fim = mid-1;
        else ini = mid+1;
    }
    return ans;
}

int main(void)
{
    cin >> n >> p >> q;

    for (int i = 1; i <= n; i++) cin >> num[i];

    if (p >= n || q >= n)
    {
        cout << "1\n";
        return 0;
    }

    sort(num+1, num+n+1);
    cout << busca() << "\n";
}

Compilation message

watching.cpp: In function 'int busca2(int)':
watching.cpp:14:27: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized]
     int ini = 1, fim = n, ans;
                           ^~~
watching.cpp: In function 'bool ok(int)':
watching.cpp:14:27: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized]
watching.cpp:41:26: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized]
                 dp[i][j] = busca2(num[dp[i-1][j]+1]+w-1);
                 ~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
watching.cpp: In function 'int busca()':
watching.cpp:59:12: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized]
     return ans;
            ^~~

Subtask #1
0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 504 KB Output is correct
2 Correct 3 ms 608 KB Output is correct
3 Correct 3 ms 624 KB Output is correct
4 Correct 2 ms 676 KB Output is correct
5 Correct 2 ms 676 KB Output is correct
6 Correct 3 ms 908 KB Output is correct
7 Incorrect 3 ms 1024 KB Output isn't correct
8 Halted 0 ms 0 KB -

Subtask #2
0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 1024 KB Output is correct
2 Correct 3 ms 1024 KB Output is correct
3 Execution timed out 1084 ms 12628 KB Time limit exceeded
4 Halted 0 ms 0 KB -