2017-yo-t3.cpp

#include <bits/stdc++.h>
using namespace std;

#define int long long

#define PB push_back
#define PPB pop_back
#define MK make_pair
#define ALL(V) V.begin(), V.end()
typedef pair<int, int> pii;
typedef pair<double, double> pdd;
typedef pair<string, int> psi;
typedef pair<int, pii> pipii;

constexpr int INF = 1LL << 61;
//constexpr int MOD = 1000000007;
//constexpr int MAX_N = 55;

int h, w, d, field[105][105];

signed main() {
    ios::sync_with_stdio(false);
    cin.tie(0);

    cin >> h >> w >> d;

    for (int y = 0; y < h; ++y) {
        string s;
        cin >> s;
        for (int x = 0; x < w; ++x) {
            field[x][y] = (s[x] == '#');
        }
    }

    int ans = 0;
    for (int y = 0; y < h; ++y) {
        for (int x = 0; x <= w - d; ++x) {
            bool flg = true;
            for (int i = 0; i < d; ++i) {
                if (field[x + i][y]) {
                    flg = false;
                    break;
                }
            }
            if (!flg) continue;
            ans++;
        }
    }

    for (int x = 0; x < w; ++x) {
        for (int y = 0; y <= h - d; ++y) {
            bool flg = true;
            for (int i = 0; i < d; ++i) {
                if (field[x][y + i]) {
                    flg = false;
                    break;
                }
            }
            if (!flg) continue;
            ans++;
        }
    }

    cout << ans << endl;
}