样例过了但是零分（我实在找不出来错误了，给个测试点也行）

#include<iostream>
using namespace std;
int main()
{
	int r, c, k,flag,cnt=0;
	char arr[101][101];
	cin >> r >> c >> k;
	for (int i = 1; i <= r; i++)
	{
		for (int j = 1; j <= c; j++)
		{
			cin >> arr[i][j];
		}
	}
	for (int i = 1; i <= r; i++)
	{
		for (int j = 1; j <= c - k + 1; j++)
		{
			if (arr[i][j] == '.') {
				flag = 1;
				for (int x = 1; x < k; x++)
				{
					if (arr[i][j + k] != '.') { 
						flag = 0;
						break; }
				}
				if (flag == 1) cnt++;
			}
		}
	}
	for (int i = 1; i <= c; i++)
	{
		for (int j = 1; j <= r - k + 1; j++)
		{
			if (arr[j][i] == '.') {
				flag = 1;
				for (int x = 1; x < k; x++) {
					if (arr[j + x][i] != '.') {
						flag = 0;
						break;
					}
				}
				if (flag == 1) cnt++;
			}
		}
	}
	cout << cnt;
	return 0;
}