oj.uz

Submission #594576

# Submission time Handle Problem Language Result Execution time Memory
594576 2022-07-12T17:04:25 Z piOOE Sandcastle 2 (JOI22_ho_t5) C++17
100 / 100
 1082 ms 4748 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;

    int mid[n][m], L[n][m], R[n][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 1 ms 212 KB Output is correct
2 Correct 19 ms 4624 KB Output is correct
3 Correct 23 ms 4560 KB Output is correct
4 Correct 30 ms 4616 KB Output is correct
5 Correct 20 ms 4612 KB Output is correct
6 Correct 32 ms 4624 KB Output is correct

Subtask #2
10.0 / 10.0

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

Subtask #3
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 1 ms 212 KB Output is correct
7 Correct 2 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 2 ms 340 KB Output is correct
13 Correct 5 ms 448 KB Output is correct
14 Correct 4 ms 340 KB Output is correct
15 Correct 5 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 1 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 1 ms 212 KB Output is correct
7 Correct 2 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 2 ms 340 KB Output is correct
13 Correct 5 ms 448 KB Output is correct
14 Correct 4 ms 340 KB Output is correct
15 Correct 5 ms 340 KB Output is correct
16 Correct 4 ms 340 KB Output is correct
17 Correct 3 ms 852 KB Output is correct
18 Correct 35 ms 852 KB Output is correct
19 Correct 12 ms 964 KB Output is correct
20 Correct 10 ms 852 KB Output is correct
21 Correct 26 ms 852 KB Output is correct
22 Correct 35 ms 852 KB Output is correct
23 Correct 34 ms 852 KB Output is correct
24 Correct 29 ms 784 KB Output is correct
25 Correct 41 ms 852 KB Output is correct
26 Correct 44 ms 852 KB Output is correct
27 Correct 46 ms 904 KB Output is correct
28 Correct 50 ms 852 KB Output is correct

Subtask #5
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 0 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 212 KB Output is correct
6 Correct 1 ms 212 KB Output is correct
7 Correct 2 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 2 ms 340 KB Output is correct
13 Correct 5 ms 448 KB Output is correct
14 Correct 4 ms 340 KB Output is correct
15 Correct 5 ms 340 KB Output is correct
16 Correct 4 ms 340 KB Output is correct
17 Correct 3 ms 852 KB Output is correct
18 Correct 35 ms 852 KB Output is correct
19 Correct 12 ms 964 KB Output is correct
20 Correct 10 ms 852 KB Output is correct
21 Correct 26 ms 852 KB Output is correct
22 Correct 35 ms 852 KB Output is correct
23 Correct 34 ms 852 KB Output is correct
24 Correct 29 ms 784 KB Output is correct
25 Correct 41 ms 852 KB Output is correct
26 Correct 44 ms 852 KB Output is correct
27 Correct 46 ms 904 KB Output is correct
28 Correct 50 ms 852 KB Output is correct
29 Correct 24 ms 4620 KB Output is correct
30 Correct 273 ms 4440 KB Output is correct
31 Correct 1067 ms 4476 KB Output is correct
32 Correct 26 ms 4748 KB Output is correct
33 Correct 159 ms 4480 KB Output is correct
34 Correct 482 ms 4448 KB Output is correct
35 Correct 370 ms 3140 KB Output is correct
36 Correct 563 ms 4440 KB Output is correct
37 Correct 1020 ms 4464 KB Output is correct
38 Correct 1020 ms 4472 KB Output is correct
39 Correct 1082 ms 4464 KB Output is correct
40 Correct 1047 ms 4432 KB Output is correct
41 Correct 1037 ms 4432 KB Output is correct
42 Correct 1002 ms 4432 KB Output is correct
43 Correct 1036 ms 4432 KB Output is correct
44 Correct 999 ms 4424 KB Output is correct