Submission #312368

# Submission time Handle Problem Language Result Execution time Memory
312368 2020-10-13T05:09:32 Z VROOM_VARUN Sparklers (JOI17_sparklers) C++14
100 / 100
76 ms 3172 KB
/*
ID: varunra2
LANG: C++
TASK: sparklers
*/

#include <bits/stdc++.h>
using namespace std;

#ifdef DEBUG
#include "lib/debug.h"
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#define debug_arr(...) \
  cerr << "[" << #__VA_ARGS__ << "]:", debug_arr(__VA_ARGS__)
#pragma GCC diagnostic ignored "-Wsign-compare"
//#pragma GCC diagnostic ignored "-Wunused-parameter"
//#pragma GCC diagnostic ignored "-Wunused-variable"
#else
#define debug(...) 42
#endif

#define int long long
#define EPS 1e-9
#define IN(A, B, C) assert(B <= A && A <= C)
#define INF (int)1e9
#define MEM(a, b) memset(a, (b), sizeof(a))
#define MOD 1000000007
#define MP make_pair
#define PB push_back
#define all(cont) cont.begin(), cont.end()
#define rall(cont) cont.end(), cont.begin()
#define x first
#define y second

const double PI = acos(-1.0);
typedef long long ll;
typedef long double ld;
typedef pair<int, int> PII;
typedef map<int, int> MPII;
typedef multiset<int> MSETI;
typedef set<int> SETI;
typedef set<string> SETS;
typedef vector<int> VI;
typedef vector<PII> VII;
typedef vector<VI> VVI;
typedef vector<string> VS;

#define rep(i, a, b) for (int i = a; i < (b); ++i)
#define trav(a, x) for (auto& a : x)
#define sz(x) (int)(x).size()
typedef pair<int, int> pii;
typedef vector<int> vi;
#pragma GCC diagnostic ignored "-Wsign-compare"
// util functions
// const int N = 1005;
int n, k, t;
int v;
VI vals;
// VVI dp(N, VI(N, -1));

void init() { vals.resize(n); }

// bool solve(int l, int r) {
//   if (l > k) return false;
//   if (r < k) return false;
//   if (l == r) return true;

//   if (dp[l][r] != -1) return dp[l][r];

//   if (vals[r] - vals[l] <= 2 * (r - l) * t * v) {
//     if (solve(l, r - 1))
//       dp[l][r] = 1;
//     else if (solve(l + 1, r))
//       dp[l][r] = 1;
//     else
//       dp[l][r] = 0;
//   } else {
//     dp[l][r] = 0;
//   }

//   return dp[l][r];
// }

// void fll(VVI& dp, int val) { trav(x, dp) trav(y, x) y = val; }

bool check(VI& a, VI& b) {
  int l1, l2, r1, r2;

  l1 = l2 = r1 = r2 = 0;

  bool moved = true;

  while (moved) {
    moved = false;
    while (l2 + 1 < sz(a) and a[l2 + 1] >= b[r1]) {
      moved = true;
      if (a[++l2] > a[l1]) l1 = l2;
    }
    while (r2 + 1 < sz(b) and a[l1] >= b[r2 + 1]) {
      moved = true;
      if (b[++r2] < b[r1]) r1 = r2;
    }
  }

  return l2 + 1 == sz(a) and r2 + 1 == sz(b);
}

bool works(int _v) {
  v = _v;
  if (v * t >= vals.back()) return true;
  VI a, b;

  for (int i = k; i >= 0; i--) {
    a.PB(vals[i] - 2 * v * t * i);
  }

  for (int i = k; i < n; i++) {
    b.PB(vals[i] - 2 * v * t * i);
  }

  if (!check(a, b)) return false;
  reverse(all(a));
  reverse(all(b));
  if (!check(a, b)) return false;
  return true;

  // // fll(dp, -1);
  // dp[k][k] = 1;
  // return solve(0, n - 1);
}

int32_t main() {
  // #ifndef ONLINE_JUDGE
  // freopen("sparklers.in", "r", stdin);
  // freopen("sparklers.out", "w", stdout);
  // #endif
  cin.sync_with_stdio(0);
  cin.tie(0);

  cin >> n >> k >> t;

  k--;

  init();

  for (int i = 0; i < n; i++) {
    cin >> vals[i];
  }

  int x = -1;

  for (int b = INF + 1; b >= 1; b /= 2) {
    while (!works(x + b)) x += b;
  }

  cout << x + 1 << '\n';

  return 0;
}
# Verdict Execution time Memory Grader output
1 Correct 1 ms 384 KB Output is correct
2 Correct 0 ms 384 KB Output is correct
3 Correct 0 ms 384 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 1 ms 384 KB Output is correct
8 Correct 0 ms 384 KB Output is correct
9 Correct 0 ms 384 KB Output is correct
10 Correct 1 ms 384 KB Output is correct
11 Correct 0 ms 384 KB Output is correct
12 Correct 1 ms 384 KB Output is correct
13 Correct 0 ms 384 KB Output is correct
14 Correct 0 ms 384 KB Output is correct
15 Correct 1 ms 384 KB Output is correct
16 Correct 1 ms 256 KB Output is correct
17 Correct 0 ms 384 KB Output is correct
18 Correct 0 ms 384 KB Output is correct
19 Correct 1 ms 256 KB Output is correct
20 Correct 0 ms 384 KB Output is correct
21 Correct 1 ms 384 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 384 KB Output is correct
2 Correct 0 ms 384 KB Output is correct
3 Correct 0 ms 384 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 1 ms 384 KB Output is correct
8 Correct 0 ms 384 KB Output is correct
9 Correct 0 ms 384 KB Output is correct
10 Correct 1 ms 384 KB Output is correct
11 Correct 0 ms 384 KB Output is correct
12 Correct 1 ms 384 KB Output is correct
13 Correct 0 ms 384 KB Output is correct
14 Correct 0 ms 384 KB Output is correct
15 Correct 1 ms 384 KB Output is correct
16 Correct 1 ms 256 KB Output is correct
17 Correct 0 ms 384 KB Output is correct
18 Correct 0 ms 384 KB Output is correct
19 Correct 1 ms 256 KB Output is correct
20 Correct 0 ms 384 KB Output is correct
21 Correct 1 ms 384 KB Output is correct
22 Correct 1 ms 384 KB Output is correct
23 Correct 1 ms 384 KB Output is correct
24 Correct 1 ms 384 KB Output is correct
25 Correct 1 ms 384 KB Output is correct
26 Correct 1 ms 384 KB Output is correct
27 Correct 1 ms 384 KB Output is correct
28 Correct 1 ms 384 KB Output is correct
29 Correct 1 ms 384 KB Output is correct
30 Correct 1 ms 384 KB Output is correct
31 Correct 1 ms 384 KB Output is correct
32 Correct 1 ms 384 KB Output is correct
33 Correct 1 ms 384 KB Output is correct
34 Correct 1 ms 384 KB Output is correct
35 Correct 1 ms 384 KB Output is correct
36 Correct 1 ms 384 KB Output is correct
37 Correct 1 ms 384 KB Output is correct
38 Correct 1 ms 384 KB Output is correct
39 Correct 2 ms 384 KB Output is correct
40 Correct 0 ms 384 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 384 KB Output is correct
2 Correct 0 ms 384 KB Output is correct
3 Correct 0 ms 384 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 1 ms 384 KB Output is correct
8 Correct 0 ms 384 KB Output is correct
9 Correct 0 ms 384 KB Output is correct
10 Correct 1 ms 384 KB Output is correct
11 Correct 0 ms 384 KB Output is correct
12 Correct 1 ms 384 KB Output is correct
13 Correct 0 ms 384 KB Output is correct
14 Correct 0 ms 384 KB Output is correct
15 Correct 1 ms 384 KB Output is correct
16 Correct 1 ms 256 KB Output is correct
17 Correct 0 ms 384 KB Output is correct
18 Correct 0 ms 384 KB Output is correct
19 Correct 1 ms 256 KB Output is correct
20 Correct 0 ms 384 KB Output is correct
21 Correct 1 ms 384 KB Output is correct
22 Correct 1 ms 384 KB Output is correct
23 Correct 1 ms 384 KB Output is correct
24 Correct 1 ms 384 KB Output is correct
25 Correct 1 ms 384 KB Output is correct
26 Correct 1 ms 384 KB Output is correct
27 Correct 1 ms 384 KB Output is correct
28 Correct 1 ms 384 KB Output is correct
29 Correct 1 ms 384 KB Output is correct
30 Correct 1 ms 384 KB Output is correct
31 Correct 1 ms 384 KB Output is correct
32 Correct 1 ms 384 KB Output is correct
33 Correct 1 ms 384 KB Output is correct
34 Correct 1 ms 384 KB Output is correct
35 Correct 1 ms 384 KB Output is correct
36 Correct 1 ms 384 KB Output is correct
37 Correct 1 ms 384 KB Output is correct
38 Correct 1 ms 384 KB Output is correct
39 Correct 2 ms 384 KB Output is correct
40 Correct 0 ms 384 KB Output is correct
41 Correct 43 ms 1800 KB Output is correct
42 Correct 2 ms 384 KB Output is correct
43 Correct 10 ms 772 KB Output is correct
44 Correct 76 ms 3048 KB Output is correct
45 Correct 67 ms 2600 KB Output is correct
46 Correct 74 ms 3172 KB Output is correct
47 Correct 72 ms 3040 KB Output is correct
48 Correct 63 ms 2540 KB Output is correct
49 Correct 74 ms 3056 KB Output is correct
50 Correct 64 ms 2488 KB Output is correct
51 Correct 74 ms 3040 KB Output is correct
52 Correct 71 ms 2908 KB Output is correct
53 Correct 70 ms 3052 KB Output is correct
54 Correct 69 ms 2848 KB Output is correct
55 Correct 70 ms 2600 KB Output is correct
56 Correct 76 ms 3064 KB Output is correct
57 Correct 72 ms 2968 KB Output is correct
58 Correct 66 ms 2540 KB Output is correct
59 Correct 7 ms 1152 KB Output is correct
60 Correct 71 ms 2872 KB Output is correct
61 Correct 61 ms 2816 KB Output is correct
62 Correct 72 ms 3056 KB Output is correct
63 Correct 70 ms 2824 KB Output is correct
64 Correct 64 ms 2552 KB Output is correct
65 Correct 65 ms 2668 KB Output is correct
66 Correct 64 ms 2672 KB Output is correct
67 Correct 65 ms 2552 KB Output is correct
68 Correct 73 ms 2864 KB Output is correct
69 Correct 68 ms 2868 KB Output is correct