oj.uz

Submission #771807

# Submission time Handle Problem Language Result Execution time Memory
771807 2023-07-03T09:38:36 Z drdilyor Radio Towers (IOI22_towers) C++17
17 / 100
 1754 ms 33816 KB 
#include <bits/stdc++.h>
#include "towers.h"
using namespace std;
using ll = long long;
constexpr int inf = 1e9;

template<typename T, typename Op>
struct SparseTable {
    vector<vector<T>> sparse;
    Op accum_func;

    SparseTable() = default;

    SparseTable(const vector<T>& arr, const Op func) : accum_func(func) {
        int n = arr.size();
        int logn = 32 - __builtin_clz(n);
        sparse.resize(logn, vector<T>(n));
        sparse[0] = arr;
        for (int lg = 1; lg < logn; lg++) {
            for (int i = 0; i + (1 << lg) <= n; i++) {
                sparse[lg][i] = accum_func(sparse[lg - 1][i], sparse[lg - 1][i + (1 << (lg - 1))]);
            }
        }
    }

    T find(int l, int r) { // [l, r]
        r++;
        int cur_log = 31 - __builtin_clz(r - l);
        return accum_func(sparse[cur_log][l], sparse[cur_log][r - (1 << cur_log)]);
    }
};

struct SegmentTree {
    using T = vector<int>;
    using S = int;
    const T id = {};
    inline T single(S v) { return {v}; }

    T merge(const T& l, const T& r) {
        T res(l.size() + r.size());
        std::merge(l.cbegin(), l.cend(),
              r.cbegin(), r.cend(),
              res.begin());
        return res;
    }

    int n;
    vector<T> tree;

    SegmentTree() = default;
    void init(vector<S> arr) {
        n = arr.size();
        while (n & (n-1)) n++;
        tree.resize(n * 2, id);
        for (int i = 0; i < (int)arr.size(); i++) {
            tree[i + n] = single(arr[i]);
        }
        build();
    }

    void build() {
        for (int i = n-1; i >= 1; i--) {
            tree[i] = merge(tree[i*2], tree[i*2 + 1]);
        }
    }

    void update(int i, S v) {
        tree[i+=n] = single(v);
        for (i /= 2; i >= 1; i/= 2)
            tree[i] = merge(tree[i*2], tree[i*2+1]);
    }

    int query(int l, int r, int x) {
        int cnt = 0;
        l += n; r += n;
        while (l <= r) {
            if (l % 2 == 1) {
                cnt += count_ge(tree[l++], x);
            }
            if (r % 2 == 0) {
                cnt += count_ge(tree[r--], x);
            }
            l /= 2; r /= 2;
        }
        return cnt;
    }

    int count_ge(T& v, int x) {
        return v.end() - lower_bound(v.begin(), v.end(), x);
    }

    int leftmost(int v, int x) {
        if (tree[v].back() < x) return -1;
        while (v < n) {
            if (tree[v*2].back() >= x) v = v * 2;
            else v = v * 2 + 1;
        }
        return v - n;
    }

    int rightmost(int v, int x) {
        if (tree[v].back() < x) return -1;
        while (v < n) {
            if (tree[v*2+1].size() && tree[v*2+1].back() >= x) v = v * 2 + 1;
            else v = v * 2;
        }
        return v - n;
    }


    int find_leftmost(int l, int r, int x, int v, int tl, int tr) {
        if (l <= tl && tr <= r) return leftmost(v, x);
        if (tr < l || r < tl) return -1;
        int mid = (tl+tr) / 2;
        int ans = find_leftmost(l, r, x, v * 2, tl, mid);
        if (ans != -1) return ans;
        return find_leftmost(l, r, x, v * 2 + 1, mid+1, tr);
    }

    int find_rightmost(int l, int r, int x, int v, int tl, int tr) {
        if (l <= tl && tr <= r) return rightmost(v, x);
        if (tr < l || r < tl) return -1;
        int mid = (tl+tr) / 2;
        int ans = find_rightmost(l, r, x, v * 2 + 1, mid+1, tr);
        if (ans != -1) return ans;
        return find_rightmost(l, r, x, v * 2, tl, mid);
    }

    int find_leftmost(int l, int r, int x) {
        return find_leftmost(l, r, x, 1, 0, n-1);
    }
    int find_rightmost(int l, int r, int x) {
        return find_rightmost(l, r, x, 1, 0, n-1);
    }
};


int st_min(int a, int b) { return min(a, b); }
int st_max(int a, int b) { return max(a, b); }

int n;
vector<int> h, ix;
SparseTable<int, decltype(&st_min)> hmax;
SparseTable<int, decltype(&st_max)> hmin;

vector<int> start;
SegmentTree ans;

int find_left(int i, int d) {
    int l = -1, r = i;
    while (l < r-1) {
        int mid = (l+r) / 2;
        if (hmax.find(mid, i) - h[i] >= d)
            l = mid;
        else r = mid;
    }
    return l;
}

int find_right(int i, int d) {
    int l = i, r = n;
    while (l < r-1) {
        int mid = (l+r) / 2;
        if (hmax.find(i, mid) - h[i] >= d)
            r = mid;
        else l = mid;
    }
    return r;
}

void init(int N, std::vector<int> H) {
    n = N, h = H;
    ix.resize(n);
    start.resize(n);
    iota(ix.begin(), ix.end(), 0);
    sort(ix.begin(), ix.end(), [&](int i, int j) {
            return h[i] < h[j];
            });
    hmax = SparseTable(h, st_max);
    hmin = SparseTable(h, st_min);
    for (int i = 0; i < n;i++) {
        int lD = 0, rD = inf+1;
        while (lD < rD-1) {
            int D = (lD + rD) / 2;
            bool ok = 1;

            int lg = find_left(i, D);
            if (hmin.find(lg+1, i) < h[i]) ok = 0;

            int rg = find_right(i, D);
            if (hmin.find(i, rg-1) < h[i]) ok = 0;

            if (ok) lD = D;
            else rD = D;
        }
        start[i] = lD;
    }
    ans.init(start);
    // for (int i : H) cout << i << ' '; cout << endl;
    // for (int i : start) cout << i << ' '; cout << endl;
}

int max_towers(int L, int R, int D) {
    int cnt = ans.query(L, R, D);
    int left = ans.find_leftmost(L, R, D);
    int right = ans.find_rightmost(L, R, D);
    int lg = left == -1 ? -1 : find_left(left, D);
    int rg = right == -1 ? n : find_right(right, D);
    // cout << cnt << ' ' << left << ' ' << right << '\n'; cout << lg << ' ' << rg << endl;
    if (lg > L && hmin.find(L, lg) <= h[lg]-D) cnt++;
    if (rg < R && hmin.find(rg, R) <= h[rg]-D) cnt++;
    return max(1, cnt);
}

Subtask #1
0 / 4.0

# Verdict Execution time Memory Grader output
1 Incorrect 921 ms 18952 KB 12th lines differ - on the 1st token, expected: '2', found: '1'
2 Halted 0 ms 0 KB -

Subtask #2
0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 336 KB Output is correct
2 Correct 10 ms 720 KB Output is correct
3 Correct 13 ms 720 KB Output is correct
4 Correct 10 ms 720 KB Output is correct
5 Correct 11 ms 764 KB Output is correct
6 Correct 10 ms 768 KB Output is correct
7 Incorrect 11 ms 720 KB 1st lines differ - on the 1st token, expected: '34', found: '33'
8 Halted 0 ms 0 KB -

Subtask #3
0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 336 KB Output is correct
2 Correct 10 ms 720 KB Output is correct
3 Correct 13 ms 720 KB Output is correct
4 Correct 10 ms 720 KB Output is correct
5 Correct 11 ms 764 KB Output is correct
6 Correct 10 ms 768 KB Output is correct
7 Incorrect 11 ms 720 KB 1st lines differ - on the 1st token, expected: '34', found: '33'
8 Halted 0 ms 0 KB -

Subtask #4
0 / 14.0

# Verdict Execution time Memory Grader output
1 Incorrect 1754 ms 33628 KB 29th lines differ - on the 1st token, expected: '9839', found: '9838'
2 Halted 0 ms 0 KB -

Subtask #5
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 422 ms 7812 KB Output is correct
2 Correct 1610 ms 33768 KB Output is correct
3 Correct 1738 ms 33772 KB Output is correct
4 Correct 1640 ms 33756 KB Output is correct
5 Correct 1667 ms 33756 KB Output is correct
6 Correct 1465 ms 33764 KB Output is correct
7 Correct 1569 ms 33764 KB Output is correct
8 Correct 1601 ms 33816 KB Output is correct
9 Correct 1542 ms 33768 KB Output is correct
10 Correct 1517 ms 33760 KB Output is correct
11 Correct 1595 ms 33768 KB Output is correct
12 Correct 811 ms 33760 KB Output is correct
13 Correct 877 ms 33764 KB Output is correct
14 Correct 845 ms 33764 KB Output is correct
15 Correct 788 ms 33768 KB Output is correct
16 Correct 785 ms 33760 KB Output is correct
17 Correct 790 ms 32868 KB Output is correct
18 Correct 816 ms 33764 KB Output is correct
19 Correct 811 ms 33760 KB Output is correct
20 Correct 808 ms 33760 KB Output is correct
21 Correct 813 ms 33764 KB Output is correct
22 Correct 833 ms 33764 KB Output is correct
23 Correct 820 ms 33764 KB Output is correct
24 Correct 776 ms 33760 KB Output is correct
25 Correct 766 ms 33780 KB Output is correct
26 Correct 775 ms 33764 KB Output is correct
27 Correct 797 ms 33764 KB Output is correct
28 Correct 10 ms 736 KB Output is correct
29 Correct 10 ms 720 KB Output is correct
30 Correct 10 ms 720 KB Output is correct
31 Correct 10 ms 848 KB Output is correct
32 Correct 10 ms 764 KB Output is correct
33 Correct 4 ms 464 KB Output is correct
34 Correct 10 ms 768 KB Output is correct
35 Correct 10 ms 772 KB Output is correct
36 Correct 10 ms 768 KB Output is correct
37 Correct 10 ms 720 KB Output is correct
38 Correct 10 ms 764 KB Output is correct
39 Correct 10 ms 720 KB Output is correct
40 Correct 11 ms 772 KB Output is correct
41 Correct 10 ms 720 KB Output is correct
42 Correct 10 ms 768 KB Output is correct
43 Correct 10 ms 720 KB Output is correct

Subtask #6
0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 336 KB Output is correct
2 Correct 10 ms 720 KB Output is correct
3 Correct 13 ms 720 KB Output is correct
4 Correct 10 ms 720 KB Output is correct
5 Correct 11 ms 764 KB Output is correct
6 Correct 10 ms 768 KB Output is correct
7 Incorrect 11 ms 720 KB 1st lines differ - on the 1st token, expected: '34', found: '33'
8 Halted 0 ms 0 KB -

Subtask #7
0 / 23.0

# Verdict Execution time Memory Grader output
1 Incorrect 921 ms 18952 KB 12th lines differ - on the 1st token, expected: '2', found: '1'
2 Halted 0 ms 0 KB -