oj.uz

Submission #1064427

# Submission time Handle Problem Language Result Execution time Memory
1064427 2024-08-18T12:34:40 Z Boycl07 Watching (JOI13_watching) C++17
100 / 100
 193 ms 32084 KB 
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;

#define int ll
#define rep(i, n) for(int i = 1; (i) <= (n); ++i)
#define forn(i, l, r) for(int i = (l); i <= (r); ++i)
#define ford(i, r, l) for(int i = (r); i >= (l); --i)
#define FOR(i, n) for(int i = 0; i < (n); ++i)
#define FORD(i, n) for(int i = ((n) - 1); i >= 0; --i)
#define fi first
#define se second
#define pii pair<int, int>
#define pll pair<ll, ll>
#define pb push_back
#define endl "\n"
#define task "FFILL"
#define sz(a) int(a.size())
#define C(x, y) make_pair(x, y)
#define all(a) (a).begin(), (a).end()
#define bit(i, mask) (mask >> i & 1)

template<typename T> bool maximize(T &res, const T &val) { if (res < val){ res = val; return true; }; return false; }
template<typename T> bool minimize(T &res, const T &val) { if (res > val){ res = val; return true; }; return false; }


const int N = 2e3 + 3;
const int LIM = (1 << 16) + 3;
const int INF = 1e9 + 1;
const int LOG = 16;

int n, p, q;

int a[N];
int dp[N][N];

bool check(int w)
{
    forn(i, 0, n) forn(j, 0, p) dp[i][j] = INF;
    dp[0][0] = 0;
    int pos_w = 1, pos_2w = 1;
    rep(i, n)
    {
        while(pos_w <= n && a[pos_w] - a[i] + 1<= w) ++pos_w;
        while(pos_2w <= n && a[pos_2w] - a[i] + 1 <= 2 * w) ++pos_2w;

        forn(j, 0, p)
        {
            minimize(dp[pos_w - 1][j + 1], dp[i - 1][j]);
            minimize(dp[pos_2w - 1][j], dp[i - 1][j] + 1);
        }
    }

    forn(j, 0, p) if(dp[n][j] <= q) return 1;
    return 0;
}

void solve()
{
    cin >> n >> p >> q;
    rep(i, n) cin >> a[i];
    sort(a + 1, a + 1 + n);
    p = min(p, n);
    q = min(q, n);

    int l = 1, r = 1e9, res;
    while(l <= r)
    {
        int mid = l + r >> 1;
        if(check(mid)) res = mid, r = mid - 1;
        else l = mid + 1;
    }

    cout << res;
}

signed main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

    int TC = 1;

    if(fopen("note.inp", "r"))
    {
        freopen("note.inp", "r", stdin);
        freopen("note.out", "w", stdout);
    }


    while(TC--)
    {
        solve();
    }

    return 0;
}

Compilation message

watching.cpp: In function 'void solve()':
watching.cpp:70:21: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   70 |         int mid = l + r >> 1;
      |                   ~~^~~
watching.cpp: In function 'int main()':
watching.cpp:87:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   87 |         freopen("note.inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
watching.cpp:88:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   88 |         freopen("note.out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 860 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 856 KB Output is correct
5 Correct 0 ms 860 KB Output is correct
6 Correct 1 ms 860 KB Output is correct
7 Correct 0 ms 860 KB Output is correct
8 Correct 0 ms 860 KB Output is correct
9 Correct 1 ms 860 KB Output is correct
10 Correct 0 ms 860 KB Output is correct
11 Correct 1 ms 860 KB Output is correct
12 Correct 1 ms 860 KB Output is correct
13 Correct 1 ms 860 KB Output is correct
14 Correct 1 ms 860 KB Output is correct
15 Correct 1 ms 860 KB Output is correct

Subtask #2
50.0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 8540 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 152 ms 32084 KB Output is correct
4 Correct 181 ms 31836 KB Output is correct
5 Correct 12 ms 9560 KB Output is correct
6 Correct 192 ms 31836 KB Output is correct
7 Correct 6 ms 8536 KB Output is correct
8 Correct 18 ms 10332 KB Output is correct
9 Correct 74 ms 20140 KB Output is correct
10 Correct 193 ms 31832 KB Output is correct
11 Correct 14 ms 9820 KB Output is correct
12 Correct 93 ms 23644 KB Output is correct
13 Correct 5 ms 8540 KB Output is correct
14 Correct 6 ms 8840 KB Output is correct
15 Correct 6 ms 8796 KB Output is correct