#include <bits/stdc++.h>
using namespace std;
#pragma GCC target("avx2")
#pragma GCC optimization("unroll-loops")
#pragma GCC optimize("O2")
constexpr int dx[] = {-1, 0, 1, 0, 1, 1, -1, -1};
constexpr int dy[] = {0, -1, 0, 1, 1, -1, 1, -1};
constexpr long long INF = 1999999999999999997;
constexpr int inf = INT_MAX;
constexpr int MAXSIZE = int(1e6) + 5;
constexpr auto PI = 3.14159265358979323846L;
constexpr auto oo = numeric_limits<int>::max() / 2 - 2;
constexpr auto eps = 1e-6;
constexpr auto mod = 1000000007;
constexpr auto MOD = 1000000007;
constexpr auto MOD9 = 1000000009;
constexpr auto maxn = 100006;
void fastio() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
}
int n, m, k;
int fre;
char a[502][502];
int x = -1, y = -1;
bool visited[502][502];
int l;
void dfs(int x, int y) {
  if (l == 0) return;
  if (x + 1 < n && a[x + 1][y] == '.' && !visited[x + 1][y] && l > 0) {
    visited[x + 1][y] = 1;
    l--;
    dfs(x + 1, y);
  }
  if (l == 0) return;
  if (y + 1 < m && a[x][y + 1] == '.' && !visited[x][y + 1] && l > 0) {
    visited[x][y + 1] = 1;
    l--;
    dfs(x, y + 1);
  }
  if (l == 0) return;
  if (x - 1 >= 0 && a[x - 1][y] == '.' && !visited[x - 1][y] && l > 0) {
    visited[x - 1][y] = 1;
    l--;
    dfs(x - 1, y);
  }
  if (l == 0) return;
  if (y - 1 < n && a[x][y - 1] == '.' && !visited[x][y - 1] && l > 0) {
    visited[x][y - 1] = 1;
    l--;
    dfs(x, y - 1);
  }
  if (l == 0) return;
}
int main() {
  fastio();
  cin >> n >> m >> k;
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      cin >> a[i][j];
      if (a[i][j] == '.') {
        fre++;
        if (x == -1) {
          x = i, y = j;
        }
      }
    }
  }
  l = fre - k;
  int c = k;
  dfs(x, y);
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      if (a[i][j] == '.' && !visited[i][j] && c > 0) {
        a[i][j] = 'X';
        c--;
      }
      cout << a[i][j];
    }
    cout << "\n";
  }
}
