Submission #771434

# Submission time Handle Problem Language Result Execution time Memory
771434 2023-07-03T02:23:51 Z PurpleCrayon Radio Towers (IOI22_towers) C++17
17 / 100
920 ms 24208 KB
#include "towers.h"
#include <bits/stdc++.h>
using namespace std;

#define sz(v) int(v.size())
#define ar array
typedef long long ll;
const int N = 1e5+10, MOD = 1e9+7;
const ll INF = 1e18+10;
const int L = 20;

int n, a[N], st[N][L];
vector<pair<int, int>> store;

void build_rmq() {
    for (int i = 0; i < n; i++) st[i][0] = a[i];
    for (int k = 2, l = 1; k <= n; k *= 2, l++) {
        for (int i = 0; i + k <= n; i++) {
            st[i][l] = max(st[i][l-1], st[i + k / 2][l-1]);
        }
    }
}

int qry_max(int l, int r) {
    int len = r - l + 1;
    int use = 31 - __builtin_clz(len);
    return max(st[l][use], st[r - (1 << use) + 1][use]);
    /*
    int ans = 0;
    for (int i = l; i <= r; i++) ans = max(ans, a[i]);
    return ans;
    */
}

void init(int _n, vector<int> H) {
    n = _n;
    for (int i = 0; i < n; i++) {
        a[i] = H[i];
    }
    build_rmq();

    set<int> s;
    for (int i = 0; i < n; i++) {
        bool use = 1;
        if (i && a[i-1] < a[i]) use = 0;
        if (i < n-1 && a[i+1] < a[i]) use = 0;
        if (use) s.insert(i);
    }

    auto f = [&](int i) {
        auto it = s.lower_bound(i); assert(*it == i);
        --it;
        return qry_max(*it, i) - max(a[*it], a[i]);
    };

    set<pair<int, int>> q;
    auto get_v = [&](int x) {
        return pair<int, int>{f(x), x};
    };

    for (auto it = next(s.begin()); it != s.end(); it++) {
        q.insert(get_v(*it));
    }

    vector<pair<int, int>> v;
    v.emplace_back(0, sz(s)); // d > 0, ans = sz(s)
    while (sz(q)) {
        auto [d, i] = *q.begin(); q.erase(q.begin());
        v.emplace_back(d, -1); // need to update v.back().second

        auto it = s.lower_bound(i); assert(*it == i);
        int one = i;
        int two = *prev(it);
        if (next(it) != s.end()) {
            q.erase(get_v(*next(it)));
        }

        if (prev(it) != s.begin()) {
            q.erase(get_v(two));
        }

        if (a[one] > a[two]) {
            s.erase(one);
            it = s.lower_bound(two);
            if (next(it) != s.end()) {
                q.insert(get_v(*next(it)));
            }
            if (it != s.begin()) {
                q.insert(get_v(*it));
            }
        } else {
            s.erase(two);
            it = s.lower_bound(one);
            if (next(it) != s.end()) {
                q.insert(get_v(*next(it)));
            }
            if (it != s.begin()) {
                q.insert(get_v(*it));
            }
        }

        v.back().second = sz(s);
    }

    store.push_back(v[0]);
    for (int i = 1; i < sz(v); i++) {
        if (v[i].first <= store.back().first) {
            store.back().second = v[i].second;
        } else {
            store.push_back(v[i]);
        }
    }
}

int max_towers(int l, int r, int d) {
    assert(l == 0 && r == n-1);
    // find the last thing < d
    int i = lower_bound(store.begin(), store.end(), pair<int, int>{d, -1}) - store.begin() - 1;
    return store[i].second;
}
# Verdict Execution time Memory Grader output
1 Runtime error 14 ms 10848 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 1 ms 464 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 1 ms 464 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 92 ms 24208 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 249 ms 3244 KB Output is correct
2 Correct 682 ms 12988 KB Output is correct
3 Correct 753 ms 13060 KB Output is correct
4 Correct 920 ms 14624 KB Output is correct
5 Correct 646 ms 14536 KB Output is correct
6 Correct 735 ms 14608 KB Output is correct
7 Correct 718 ms 14628 KB Output is correct
8 Correct 546 ms 9260 KB Output is correct
9 Correct 489 ms 9280 KB Output is correct
10 Correct 755 ms 9264 KB Output is correct
11 Correct 599 ms 9296 KB Output is correct
12 Correct 91 ms 12952 KB Output is correct
13 Correct 136 ms 14612 KB Output is correct
14 Correct 128 ms 14620 KB Output is correct
15 Correct 21 ms 9280 KB Output is correct
16 Correct 16 ms 9272 KB Output is correct
17 Correct 82 ms 12368 KB Output is correct
18 Correct 95 ms 13084 KB Output is correct
19 Correct 90 ms 13040 KB Output is correct
20 Correct 129 ms 14504 KB Output is correct
21 Correct 131 ms 14628 KB Output is correct
22 Correct 147 ms 14664 KB Output is correct
23 Correct 130 ms 14624 KB Output is correct
24 Correct 14 ms 9296 KB Output is correct
25 Correct 14 ms 9260 KB Output is correct
26 Correct 14 ms 9296 KB Output is correct
27 Correct 14 ms 9276 KB Output is correct
28 Correct 2 ms 560 KB Output is correct
29 Correct 2 ms 592 KB Output is correct
30 Correct 2 ms 592 KB Output is correct
31 Correct 1 ms 556 KB Output is correct
32 Correct 1 ms 464 KB Output is correct
33 Correct 1 ms 336 KB Output is correct
34 Correct 1 ms 464 KB Output is correct
35 Correct 1 ms 464 KB Output is correct
36 Correct 2 ms 592 KB Output is correct
37 Correct 2 ms 464 KB Output is correct
38 Correct 2 ms 560 KB Output is correct
39 Correct 2 ms 592 KB Output is correct
40 Correct 1 ms 464 KB Output is correct
41 Correct 1 ms 464 KB Output is correct
42 Correct 1 ms 464 KB Output is correct
43 Correct 1 ms 464 KB Output is correct
# Verdict Execution time Memory Grader output
1 Runtime error 1 ms 464 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 14 ms 10848 KB Execution killed with signal 6
2 Halted 0 ms 0 KB -