oj.uz

Submission #594569

# Submission time Handle Problem Language Result Execution time Memory
594569 2022-07-12T17:00:48 Z piOOE Sandcastle 2 (JOI22_ho_t5) C++17
100 / 100
 996 ms 4756 KB 
#include <bits/stdc++.h>

using namespace std;

using ll = long long;

//O(min(H, W) * H * W)
//I also came up with O((H * W)^2) solution, but didn't know how to optimize it to O(min(H, W) * H * W)
//so now this is Radewoosh's solution

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int n, m;
    cin >> n >> m;

    bool swapped = false;
    if (n > m) {
        swapped = true;
        swap(n, m);
    }

    vector<vector<int>> a(n, vector<int>(m));
    vector<int> yy;
    for (int i = 0; i < (swapped ? m : n); ++i) {
        for (int j = 0; j < (swapped ? n : m); ++j) {
            if (!swapped) {
                cin >> a[i][j];
                yy.push_back(a[i][j]);
            } else {
                cin >> a[j][i];
                yy.push_back(a[j][i]);
            }
        }
    }

    sort(yy.begin(), yy.end());
    yy.resize(unique(yy.begin(), yy.end()) - yy.begin());

    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < m; ++j) {
            a[i][j] = lower_bound(yy.begin(), yy.end(), a[i][j]) - yy.begin() + 1;
        }
    }

    const int dx[4] = {-1, 0, 1, 0};
    const int dy[4] = {0, 1, 0, -1};

    int ans = 0;
    int diff[16][n][m];

    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < m; ++j) {
            for (int mask = 0; mask < 16; ++mask) {
                int lower = 0;
                bool big = false;
                for (int k = 0; k < 4; ++k) {
                    if (mask >> k & 1) {
                        int nx = i + dx[k];
                        int ny = j + dy[k];
                        if (nx >= 0 && nx < n && ny >= 0 && ny < m) {
                            if (a[nx][ny] < a[i][j]) {
                                lower = max(lower, a[nx][ny]);
                            } else {
                                big = true;
                            }
                        }
                    }
                }
                diff[mask][i][j] = a[i][j] - lower + (big ? 0 : n * m + 1 - a[i][j]);
            }
        }
    }

    //now handle rectangles with width or length = 1
    for (int k = 0; k < n; ++k) {
        for (int i = 0; i < m;) {
            int j = i + 1;
            while (j < m && a[k][j] < a[k][j - 1]) {
                j += 1;
            }
            int len = j - i;
            ans += len * ((ll) len - 1) / 2;
            i = j;
        }

        for (int i = m - 1; i > -1;) {
            int j = i - 1;
            while (j > -1 && a[k][j] < a[k][j + 1]) {
                j -= 1;
            }
            int len = i - j;
            ans += len * ((ll) len - 1) / 2;
            i = j;
        }
    }
    for (int k = 0; k < m; ++k) {
        for (int i = 0; i < n;) {
            int j = i + 1;
            while (j < n && a[j][k] < a[j - 1][k]) {
                j += 1;
            }
            int len = j - i;
            ans += len * ((ll) len - 1) / 2;
            i = j;
        }

        for (int i = n - 1; i > -1;) {
            int j = i - 1;
            while (j > -1 && a[j][k] < a[j + 1][k]) {
                j -= 1;
            }
            int len = i - j;
            ans += len * ((ll) len - 1) / 2;
            i = j;
        }
    }
    ans += n * m;

    vector<vector<int>> mid(n, vector<int>(m)), L(n, vector<int>(m)), R(n, vector<int>(m));

    for (int y = 0; y < m; ++y) {
        for (int x = 0; x < n; ++x) {
            mid[x][y] = (x ? mid[x - 1][y] : 0) + diff[15][x][y];
            L[x][y] = (x ? L[x - 1][y] : 0) + diff[7][x][y];
            R[x][y] = (x ? R[x - 1][y] : 0) + diff[13][x][y];
        }
    }

    //main part!
    for (int x1 = 0; x1 < n; ++x1) {
        for (int x2 = x1 + 1; x2 < n; ++x2) {
            vector<int> valMid(m), valR(m), valL(m);
            for (int y = 0; y < m; ++y) {
                valMid[y] = mid[x2 - 1][y] - mid[x1][y] + diff[14][x1][y] + diff[11][x2][y];
                valR[y] = R[x2 - 1][y] - R[x1][y] + diff[12][x1][y] + diff[9][x2][y];
                valL[y] = L[x2 - 1][y] - L[x1][y] + diff[6][x1][y] + diff[3][x2][y];
            }
            unordered_map<int, int> cnt;
            int prefix = 0;
            for (int y1 = 0; y1 < m; ++y1) {
                if (y1 > 0) {
                    prefix += valMid[y1 - 1];
                    ++cnt[prefix - valL[y1 - 1]];
                }
                ans += cnt[prefix + valR[y1] - (n * m + 1)];
            }
        }
    }
    cout << ans;
    return 0;
}

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 15 ms 4624 KB Output is correct
3 Correct 22 ms 4500 KB Output is correct
4 Correct 19 ms 4624 KB Output is correct
5 Correct 18 ms 4604 KB Output is correct
6 Correct 21 ms 4616 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct

Subtask #3
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 1 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 6 ms 340 KB Output is correct
10 Correct 2 ms 340 KB Output is correct
11 Correct 1 ms 340 KB Output is correct
12 Correct 1 ms 340 KB Output is correct
13 Correct 5 ms 340 KB Output is correct
14 Correct 3 ms 340 KB Output is correct
15 Correct 4 ms 340 KB Output is correct
16 Correct 4 ms 340 KB Output is correct

Subtask #4
56.0 / 56.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 1 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 6 ms 340 KB Output is correct
10 Correct 2 ms 340 KB Output is correct
11 Correct 1 ms 340 KB Output is correct
12 Correct 1 ms 340 KB Output is correct
13 Correct 5 ms 340 KB Output is correct
14 Correct 3 ms 340 KB Output is correct
15 Correct 4 ms 340 KB Output is correct
16 Correct 4 ms 340 KB Output is correct
17 Correct 2 ms 852 KB Output is correct
18 Correct 38 ms 852 KB Output is correct
19 Correct 10 ms 852 KB Output is correct
20 Correct 10 ms 908 KB Output is correct
21 Correct 22 ms 852 KB Output is correct
22 Correct 35 ms 792 KB Output is correct
23 Correct 40 ms 852 KB Output is correct
24 Correct 32 ms 724 KB Output is correct
25 Correct 47 ms 852 KB Output is correct
26 Correct 41 ms 852 KB Output is correct
27 Correct 40 ms 852 KB Output is correct
28 Correct 46 ms 852 KB Output is correct

Subtask #5
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 0 ms 212 KB Output is correct
5 Correct 0 ms 212 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 1 ms 340 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 6 ms 340 KB Output is correct
10 Correct 2 ms 340 KB Output is correct
11 Correct 1 ms 340 KB Output is correct
12 Correct 1 ms 340 KB Output is correct
13 Correct 5 ms 340 KB Output is correct
14 Correct 3 ms 340 KB Output is correct
15 Correct 4 ms 340 KB Output is correct
16 Correct 4 ms 340 KB Output is correct
17 Correct 2 ms 852 KB Output is correct
18 Correct 38 ms 852 KB Output is correct
19 Correct 10 ms 852 KB Output is correct
20 Correct 10 ms 908 KB Output is correct
21 Correct 22 ms 852 KB Output is correct
22 Correct 35 ms 792 KB Output is correct
23 Correct 40 ms 852 KB Output is correct
24 Correct 32 ms 724 KB Output is correct
25 Correct 47 ms 852 KB Output is correct
26 Correct 41 ms 852 KB Output is correct
27 Correct 40 ms 852 KB Output is correct
28 Correct 46 ms 852 KB Output is correct
29 Correct 17 ms 4624 KB Output is correct
30 Correct 280 ms 4436 KB Output is correct
31 Correct 989 ms 4424 KB Output is correct
32 Correct 18 ms 4756 KB Output is correct
33 Correct 155 ms 4432 KB Output is correct
34 Correct 457 ms 4344 KB Output is correct
35 Correct 343 ms 3028 KB Output is correct
36 Correct 553 ms 4424 KB Output is correct
37 Correct 979 ms 4432 KB Output is correct
38 Correct 957 ms 4432 KB Output is correct
39 Correct 996 ms 4432 KB Output is correct
40 Correct 963 ms 4340 KB Output is correct
41 Correct 975 ms 4432 KB Output is correct
42 Correct 983 ms 4424 KB Output is correct
43 Correct 981 ms 4432 KB Output is correct
44 Correct 993 ms 4432 KB Output is correct