Submission #594574

# Submission time Handle Problem Language Result Execution time Memory
594574 2022-07-12T17:03:57 Z piOOE Sandcastle 2 (JOI22_ho_t5) C++17
80 / 100
264 ms 9032 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!
    int mx = 0;
    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]];
                    mx = max(mx, prefix - valL[y1 - 1]);
                }
                ans += cnt[prefix + valR[y1] - (n * m + 1)];
            }
        }
    }
    assert(mx <= 100000000);
    cout << ans;
    return 0;
}
# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 17 ms 4620 KB Output is correct
3 Correct 24 ms 4552 KB Output is correct
4 Correct 19 ms 4620 KB Output is correct
5 Correct 19 ms 4608 KB Output is correct
6 Correct 22 ms 4628 KB Output is correct
# 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 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
# 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 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 2 ms 340 KB Output is correct
9 Correct 5 ms 340 KB Output is correct
10 Correct 2 ms 340 KB Output is correct
11 Correct 2 ms 340 KB Output is correct
12 Correct 1 ms 340 KB Output is correct
13 Correct 4 ms 340 KB Output is correct
14 Correct 3 ms 340 KB Output is correct
15 Correct 4 ms 352 KB Output is correct
16 Correct 4 ms 340 KB Output is correct
# 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 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 2 ms 340 KB Output is correct
9 Correct 5 ms 340 KB Output is correct
10 Correct 2 ms 340 KB Output is correct
11 Correct 2 ms 340 KB Output is correct
12 Correct 1 ms 340 KB Output is correct
13 Correct 4 ms 340 KB Output is correct
14 Correct 3 ms 340 KB Output is correct
15 Correct 4 ms 352 KB Output is correct
16 Correct 4 ms 340 KB Output is correct
17 Correct 2 ms 852 KB Output is correct
18 Correct 35 ms 908 KB Output is correct
19 Correct 11 ms 852 KB Output is correct
20 Correct 10 ms 852 KB Output is correct
21 Correct 23 ms 912 KB Output is correct
22 Correct 36 ms 852 KB Output is correct
23 Correct 39 ms 892 KB Output is correct
24 Correct 31 ms 860 KB Output is correct
25 Correct 42 ms 908 KB Output is correct
26 Correct 43 ms 916 KB Output is correct
27 Correct 43 ms 904 KB Output is correct
28 Correct 43 ms 936 KB Output is correct
# 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 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 2 ms 340 KB Output is correct
9 Correct 5 ms 340 KB Output is correct
10 Correct 2 ms 340 KB Output is correct
11 Correct 2 ms 340 KB Output is correct
12 Correct 1 ms 340 KB Output is correct
13 Correct 4 ms 340 KB Output is correct
14 Correct 3 ms 340 KB Output is correct
15 Correct 4 ms 352 KB Output is correct
16 Correct 4 ms 340 KB Output is correct
17 Correct 2 ms 852 KB Output is correct
18 Correct 35 ms 908 KB Output is correct
19 Correct 11 ms 852 KB Output is correct
20 Correct 10 ms 852 KB Output is correct
21 Correct 23 ms 912 KB Output is correct
22 Correct 36 ms 852 KB Output is correct
23 Correct 39 ms 892 KB Output is correct
24 Correct 31 ms 860 KB Output is correct
25 Correct 42 ms 908 KB Output is correct
26 Correct 43 ms 916 KB Output is correct
27 Correct 43 ms 904 KB Output is correct
28 Correct 43 ms 936 KB Output is correct
29 Correct 16 ms 4624 KB Output is correct
30 Runtime error 264 ms 9032 KB Execution killed with signal 6
31 Halted 0 ms 0 KB -