Niitty

input/code.cpp: In function 'int main()':
input/code.cpp:67:10: warning: variable 'start' set but not used [-Wunused-but-set-variable]
   67 |     auto start = chrono::high_resolution_clock::now();
      |          ^~~~~
input/code.cpp:141:10: warning: variable 'stop' set but not used [-Wunused-but-set-variable]
  141 |     auto stop = chrono::high_resolution_clock::now();
      |          ^~~~

#include <iostream>
#include <vector>
#include <chrono>
using namespace std;
using ll = long long;
 
 
int tree_size = 1;
 
int tree_range( vector<int>& tree, int a, int b ) {
    a += tree_size;
    b += tree_size;
 
    int s = 0;
 
    while (a <= b) {
        if (a%2 == 1) s |= tree[a++];
        if (b%2 == 0) s |= tree[b--];
        a /= 2; b /= 2;
    }
    return s;
}
 
 
void tree_insert ( vector<int>& tree, int x, int i ) {
    i += tree_size;
    tree[i] = x;
 
    for ( i /= 2; i >= 1; i /= 2 )
        tree[i] = tree[i*2] | tree[i*2+1];
}
 
 
 
int main () {
    int n;
    cin >> n;
    
    while ( tree_size < n )
        tree_size <<= 1;
 
 
    vector<vector<int>> field(n, vector<int>(2*tree_size, 0));
    vector<vector<int>> field_vertical(n, vector<int>(2*tree_size, 0));


    int flowers = 0;
    for ( int i = 0; i < n; ++i ) {
        for ( int j = 0; j < n; j++ ) {
            char c;
            cin >> c;
            
            int a = 1<<(c-'A');
 
            tree_insert(field[i], a, j);
            tree_insert(field_vertical[j], a, i);
            flowers |= a;

        }
    }

 
 
    ll count = 0;
 
    
    auto start = chrono::high_resolution_clock::now();
    for ( int y1 = 0; y1 < n; ++y1 ) {
        ll prevcounty = count;
        for ( int x1 = 0; x1 < n; ++x1 ) {
            int xceil = n;
            int yprev = y1;
            
            int xvals[n];
            xvals[n-1] = 0;
 
            ll prevcountx = count;
 
            while ( xceil > x1 ) {
                int x2 = xceil-1;
                int y2 = yprev;
 
                int current = xvals[x2];
                while ( y2 < n && current != flowers ) {
                    int a = x1+tree_size;
                    int b = x2+tree_size;
                
                    while (a <= b) {
                        if (a%2 == 1) current |= field[y2][a++];
                        if (b%2 == 0) current |= field[y2][b--];
                        a /= 2; b /= 2;
                    }
                    y2++;
                }
 
                if ( current != flowers )
                    break;

                y2 -= current == flowers;
                
 
                x2 = x1;
 
                current = 0;
                while ( x2 < xceil && current != flowers ) {
                    int a = y1+tree_size;
                    int b = y2+tree_size;
                
                    while (a <= b) {
                        if (a%2 == 1) current |= field_vertical[x2][a++];
                        if (b%2 == 0) current |= field_vertical[x2][b--];
                        a /= 2; b /= 2;
                    }
                    xvals[x2] = current;
                    x2++;
                }
 
                if ( current != flowers )
                    break;

                x2 -= current == flowers;
 
 
                count += ll(xceil - x2) * ll(n - y2);
                
                xceil = x2;
                yprev = y2;
            }
 
            if ( (count - prevcountx) == 0 )
                break;
        }
 
        if ( (count - prevcounty) == 0 )
            break;
    }
 
    cout << count;
    

    auto stop = chrono::high_resolution_clock::now();
    //cout << "\n" << chrono::duration_cast<chrono::milliseconds>(stop - start).count() << " ms";
}

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: ACCEPTED

Test 16

Group: 4, 5, 6

Verdict: ACCEPTED

Test 17

Group: 4, 5, 6

Verdict: ACCEPTED

Test 18

Group: 5, 6

Verdict: ACCEPTED

Test 19

Group: 5, 6

Verdict: ACCEPTED

Test 20

Group: 5, 6

Verdict: ACCEPTED

Test 21

Group: 5, 6

Verdict: ACCEPTED

Test 22

Group: 6

Verdict: ACCEPTED

Test 23

Group: 6

Verdict: ACCEPTED

Test 24

Group: 6

Verdict: ACCEPTED

Test 25

Group: 6

Verdict: TIME LIMIT EXCEEDED