Tontti

#include <iostream>
#include <math.h>
#include <stdio.h>

using namespace std;

int main() {
	cin.sync_with_stdio(false);
	int i, j, n, m, k, x, q, w, o;
	int sz, s;
	cin >> n >> m >> k;
	char input[n][m];
	int a[n*m];
	int f[n*m];
	for (i = 0; i < n; i++)
		cin >> input[i];
	sz = (int)ceil(sqrt((double)k));
	x = 0;
	for (i = 0; i < n; i++)
		for (j = 0; j < m; j++) {
			a[i*m+j] = !(input[i][j]=='.');
			f[i*m+j] = 0;
			if(k<2)
				x += a[i*m+j]^k^1;
		}
	int c = max(sz,2);
	int g = 0, h = 0, d;
	for (s = c; s <= min(n,m); s++) {
		for (i = s - 1; i < n; i++) {
			for (j = s - 1; j < m; j++) {
				d = i*m+j;
				int t = f[d];
				if (s == c) {
					if (i == j && (i == s - 1)) {
						for (q = 0; q < s; q++) {
							for (w = 0; w < s; w++) {
								t += a[q*m+w];
							}
						}
						g = h = f[d] = t;
					} else if (j >= s) {
						q = j;
						w = q - s;
						int e = i-s+1;
						for (o = 0; o < s; o++) {
							g += (a[(o+e)*m+q] - a[(o+e)*m+w]);
						}
						f[d] = t = g;
					} else {
						f[d] = t = g;
					}
				} else {
					for (q = 0; q < s - 1; q++) {
						t += a[(i-s+1)*m+j-q];
						t += a[(i-q)*m+j-s+1];
					}
					f[d] = t = (t+a[(i-s+1)*m+j-s+1]);
				}
				if (t == k) x++;
			}
			if (s == c && (i + 1) < n) {
				q = (i + 1) * m;
				w = q - s * m;
				for (o = 0; o < s; o++) {
					h += (a[q+o] - a[w+o]);
				}
				g = h;
			}
		}
	}
	cout << x << "\n";
	return 0;
}

Test 1

Group: 1

Verdict: ACCEPTED

Test 2

Group: 1

Verdict: ACCEPTED

Test 3

Group: 1

Verdict: ACCEPTED

Test 4

Group: 1

Verdict: ACCEPTED

Test 5

Group: 1

Verdict: ACCEPTED

Test 6

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 7

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 8

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 9

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 10

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 11

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 12

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 13

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 14

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 15

Group: 3

Verdict: TIME LIMIT EXCEEDED