Niitty

#include <iostream>
#include <vector>
#include <set>
#include <unordered_map>

using namespace std;

class BIT2D {
public:
    vector<vector<int>> bit;
    int n, m;

    BIT2D(int n, int m) : n(n), m(m) {
        bit.resize(n + 1, vector<int>(m + 1, 0));
    }

    void update(int x, int y, int val) {
        for (int i = x; i <= n; i += i & -i) {
            for (int j = y; j <= m; j += j & -j) {
                bit[i][j] += val;
            }
        }
    }

    int query(int x, int y) {
        int res = 0;
        for (int i = x; i > 0; i -= i & -i) {
            for (int j = y; j > 0; j -= j & -j) {
                res += bit[i][j];
            }
        }
        return res;
    }

    int query_range(int x1, int y1, int x2, int y2) {
        return query(x2, y2) - query(x1 - 1, y2) - query(x2, y1 - 1) + query(x1 - 1, y1 - 1);
    }
};

int count_fa(vector<string>& grid, int n) {
    set<char> unique_kukat;
    for (const auto& row : grid) {
        for (char kukka : row) {
            unique_kukat.insert(kukka);
        }
    }
    int total_lajit = unique_kukat.size();
    unordered_map<char, int> lajit_index;
    int idx = 0;
    for (char flower : unique_kukat) {
        lajit_index[flower] = idx++;
    }
    
    vector<BIT2D> species_bits(total_lajit, BIT2D(n, n));
    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < n; ++j) {
            char kukka = grid[i][j];
            int laji_index = lajit_index[kukka];
            species_bits[laji_index].update(i + 1, j + 1, 1); 
        }
    }

    int b = 0;

    for (int r1 = 0; r1 < n; ++r1) {
        for (int r2 = r1; r2 < n; ++r2) {
            vector<int> lajit_w(total_lajit, 0);
            int a = 0;
            int left = 0;

            for (int right = 0; right < n; ++right) {
                for (int s = 0; s < total_lajit; ++s) {
                    int count = species_bits[s].query_range(r1 + 1, right + 1, r2 + 1, right + 1);
                    if (count > 0 && lajit_w[s] == 0) {
                        a++;
                    }
                    lajit_w[s] += count;
                }
                
                while (a == total_lajit) {
                    b += (n - right);

                    for (int s = 0; s < total_lajit; ++s) {
                        int count = species_bits[s].query_range(r1 + 1, left + 1, r2 + 1, left + 1);
                        if (count > 0) {
                            lajit_w[s] -= count;
                            if (lajit_w[s] == 0) {
                                a--;
                            }
                        }
                    }
                    left++;
                }
            }
        }
    }

    return b;
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    int n;
    cin >> n;
    vector<string> meadow(n);
    for (int i = 0; i < n; ++i) {
        cin >> meadow[i];
    }

    int result = count_fa(meadow, n);
    cout << result << endl;

    return 0;
}

Test 1

Group: 1, 2, 3, 4, 5, 6

Verdict: ACCEPTED

Test 2

Group: 1, 2, 3, 4, 5, 6

Verdict: ACCEPTED

Test 3

Group: 1, 2, 3, 4, 5, 6

Verdict: ACCEPTED

Test 4

Group: 1, 2, 3, 4, 5, 6

Verdict: ACCEPTED

Test 5

Group: 1, 2, 3, 4, 5, 6

Verdict: ACCEPTED

Test 6

Group: 2, 3, 4, 5, 6

Verdict: ACCEPTED

Test 7

Group: 2, 3, 4, 5, 6

Verdict: ACCEPTED

Test 8

Group: 2, 3, 4, 5, 6

Verdict: ACCEPTED

Test 9

Group: 2, 3, 4, 5, 6

Verdict: ACCEPTED

Test 10

Group: 3, 4, 5, 6

Verdict: ACCEPTED

Test 11

Group: 3, 4, 5, 6

Verdict: ACCEPTED

Test 12

Group: 3, 4, 5, 6

Verdict: ACCEPTED

Test 13

Group: 3, 4, 5, 6

Verdict: ACCEPTED

Test 14

Group: 4, 5, 6

Verdict: ACCEPTED

Test 15

Group: 4, 5, 6

Verdict: TIME LIMIT EXCEEDED

Test 16

Group: 4, 5, 6

Verdict: ACCEPTED

Test 17

Group: 4, 5, 6

Verdict: ACCEPTED

Test 18

Group: 5, 6

Verdict: TIME LIMIT EXCEEDED

Test 19

Group: 5, 6

Verdict: TIME LIMIT EXCEEDED

Test 20

Group: 5, 6

Verdict: ACCEPTED

Test 21

Group: 5, 6

Verdict: TIME LIMIT EXCEEDED

Test 22

Group: 6

Verdict: TIME LIMIT EXCEEDED

Test 23

Group: 6

Verdict: TIME LIMIT EXCEEDED

Test 24

Group: 6

Verdict: TIME LIMIT EXCEEDED

Test 25

Group: 6

Verdict: TIME LIMIT EXCEEDED