oj.uz

Submission #69854

# Submission time Handle Problem Language Result Execution time Memory
69854 2018-08-21T16:51:46 Z Benq Sparklers (JOI17_sparklers) C++14
50 / 100
 92 ms 2804 KB 
#pragma GCC optimize ("O3")
#pragma GCC target ("sse4")

#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/rope>

using namespace std;
using namespace __gnu_pbds;
using namespace __gnu_cxx;
 
typedef long long ll;
typedef long double ld;
typedef complex<ld> cd;

typedef pair<int, int> pi;
typedef pair<ll,ll> pl;
typedef pair<ld,ld> pd;

typedef vector<int> vi;
typedef vector<ld> vd;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
typedef vector<cd> vcd;

template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;

#define FOR(i, a, b) for (int i=a; i<(b); i++)
#define F0R(i, a) for (int i=0; i<(a); i++)
#define FORd(i,a,b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i,a) for (int i = (a)-1; i >= 0; i--)

#define sz(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define f first
#define s second
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()

const int MOD = 1000000007;
const ll INF = 1e18;
const int MX = 100001;

int N,K,T,mid;
vi X;
bool ok[1000][1000][2];

// k = 0: 
// X[i-1]+t*mid 
// currently at X[i]+t*mid 
// X[j]-t*mid 
// X[j+1]-t*mid

bool OK() {
    F0Rd(i,K+1) FOR(j,K,N) F0R(k,2) ok[i][j][k] = 0;
    ok[K][K][0] = ok[K][K][1] = 1;
    F0Rd(i,K+1) FOR(j,K,N) {
        ld dis = (ld)(j-i+1)*T*2*mid;
        if (dis >= X[j]-X[i]) {
            ok[i][j][0] |= ok[i][j][1];
            ok[i][j][1] |= ok[i][j][0];
        }
        if (i && dis >= X[j]-X[i-1]) ok[i-1][j][0] |= ok[i][j][0];
        if (j < N-1 && dis >= X[j+1]-X[i]) ok[i][j+1][1] |= ok[i][j][1];
    }
    return ok[0][N-1][0] || ok[0][N-1][1];
}

int main() {
    ios_base::sync_with_stdio(0); cin.tie(0);
    cin >> N >> K >> T; X.resize(N); K--;
    F0R(i,N) cin >> X[i];
    int lo = 0, hi = 1000000000;
    while (lo < hi) {
        mid = (lo+hi)/2;
        if (OK()) hi = mid;
        else lo = mid+1;
    }
    cout << lo;
}

/* Look for:
* the exact constraints (multiple sets are too slow for n=10^6 :( ) 
* special cases (n=1?)
* overflow (ll vs int?)
* array bounds
* if you have no idea just guess the appropriate well-known algo instead of doing nothing :/
*/

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 376 KB Output is correct
2 Correct 3 ms 376 KB Output is correct
3 Correct 2 ms 560 KB Output is correct
4 Correct 8 ms 560 KB Output is correct
5 Correct 3 ms 672 KB Output is correct
6 Correct 3 ms 672 KB Output is correct
7 Correct 2 ms 672 KB Output is correct
8 Correct 3 ms 672 KB Output is correct
9 Correct 3 ms 672 KB Output is correct
10 Correct 2 ms 672 KB Output is correct
11 Correct 3 ms 704 KB Output is correct
12 Correct 3 ms 704 KB Output is correct
13 Correct 2 ms 704 KB Output is correct
14 Correct 2 ms 704 KB Output is correct
15 Correct 2 ms 704 KB Output is correct
16 Correct 2 ms 704 KB Output is correct
17 Correct 2 ms 704 KB Output is correct
18 Correct 3 ms 704 KB Output is correct
19 Correct 2 ms 704 KB Output is correct
20 Correct 3 ms 704 KB Output is correct
21 Correct 2 ms 704 KB Output is correct

Subtask #2
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 376 KB Output is correct
2 Correct 3 ms 376 KB Output is correct
3 Correct 2 ms 560 KB Output is correct
4 Correct 8 ms 560 KB Output is correct
5 Correct 3 ms 672 KB Output is correct
6 Correct 3 ms 672 KB Output is correct
7 Correct 2 ms 672 KB Output is correct
8 Correct 3 ms 672 KB Output is correct
9 Correct 3 ms 672 KB Output is correct
10 Correct 2 ms 672 KB Output is correct
11 Correct 3 ms 704 KB Output is correct
12 Correct 3 ms 704 KB Output is correct
13 Correct 2 ms 704 KB Output is correct
14 Correct 2 ms 704 KB Output is correct
15 Correct 2 ms 704 KB Output is correct
16 Correct 2 ms 704 KB Output is correct
17 Correct 2 ms 704 KB Output is correct
18 Correct 3 ms 704 KB Output is correct
19 Correct 2 ms 704 KB Output is correct
20 Correct 3 ms 704 KB Output is correct
21 Correct 2 ms 704 KB Output is correct
22 Correct 36 ms 1156 KB Output is correct
23 Correct 19 ms 1196 KB Output is correct
24 Correct 10 ms 1196 KB Output is correct
25 Correct 7 ms 1196 KB Output is correct
26 Correct 40 ms 1196 KB Output is correct
27 Correct 44 ms 1196 KB Output is correct
28 Correct 68 ms 2100 KB Output is correct
29 Correct 66 ms 2108 KB Output is correct
30 Correct 41 ms 2356 KB Output is correct
31 Correct 45 ms 2356 KB Output is correct
32 Correct 69 ms 2356 KB Output is correct
33 Correct 59 ms 2356 KB Output is correct
34 Correct 40 ms 2584 KB Output is correct
35 Correct 54 ms 2584 KB Output is correct
36 Correct 21 ms 2584 KB Output is correct
37 Correct 34 ms 2584 KB Output is correct
38 Correct 92 ms 2584 KB Output is correct
39 Correct 16 ms 2804 KB Output is correct
40 Correct 73 ms 2804 KB Output is correct

Subtask #3
0 / 50.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 376 KB Output is correct
2 Correct 3 ms 376 KB Output is correct
3 Correct 2 ms 560 KB Output is correct
4 Correct 8 ms 560 KB Output is correct
5 Correct 3 ms 672 KB Output is correct
6 Correct 3 ms 672 KB Output is correct
7 Correct 2 ms 672 KB Output is correct
8 Correct 3 ms 672 KB Output is correct
9 Correct 3 ms 672 KB Output is correct
10 Correct 2 ms 672 KB Output is correct
11 Correct 3 ms 704 KB Output is correct
12 Correct 3 ms 704 KB Output is correct
13 Correct 2 ms 704 KB Output is correct
14 Correct 2 ms 704 KB Output is correct
15 Correct 2 ms 704 KB Output is correct
16 Correct 2 ms 704 KB Output is correct
17 Correct 2 ms 704 KB Output is correct
18 Correct 3 ms 704 KB Output is correct
19 Correct 2 ms 704 KB Output is correct
20 Correct 3 ms 704 KB Output is correct
21 Correct 2 ms 704 KB Output is correct
22 Correct 36 ms 1156 KB Output is correct
23 Correct 19 ms 1196 KB Output is correct
24 Correct 10 ms 1196 KB Output is correct
25 Correct 7 ms 1196 KB Output is correct
26 Correct 40 ms 1196 KB Output is correct
27 Correct 44 ms 1196 KB Output is correct
28 Correct 68 ms 2100 KB Output is correct
29 Correct 66 ms 2108 KB Output is correct
30 Correct 41 ms 2356 KB Output is correct
31 Correct 45 ms 2356 KB Output is correct
32 Correct 69 ms 2356 KB Output is correct
33 Correct 59 ms 2356 KB Output is correct
34 Correct 40 ms 2584 KB Output is correct
35 Correct 54 ms 2584 KB Output is correct
36 Correct 21 ms 2584 KB Output is correct
37 Correct 34 ms 2584 KB Output is correct
38 Correct 92 ms 2584 KB Output is correct
39 Correct 16 ms 2804 KB Output is correct
40 Correct 73 ms 2804 KB Output is correct
41 Runtime error 16 ms 2804 KB Execution killed with signal 11 (could be triggered by violating memory limits)
42 Halted 0 ms 0 KB -