#include <bits/stdc++.h>
using namespace std;
char maze[505][505];
bool visited[505][505];
int n, m, k;
vector<pair<int, int> > v;
bool in(int x, int y) {
  if (x >= 0 && x < n && y >= 0 && y < m)
    return true;
  else
    return false;
}
int dx[] = {+1, -1, 0, 0};
int dy[] = {0, 0, -1, +1};
void dfs(int u, int v) {
  visited[u][v] = true;
  k--;
  for (int i = 0; i < 4; i++) {
    if (k > 0) {
      int x, y;
      x = u + dx[i];
      y = v + dy[i];
      if (in(x, y) && maze[x][y] == '.' && !visited[x][y]) dfs(x, y);
    }
  }
}
int main() {
  cin >> n >> m >> k;
  for (int i = 0; i < n; i++)
    for (int j = 0; j < m; j++) cin >> maze[i][j];
  for (int i = 0; i < n; i++)
    for (int j = 0; j < m; j++) {
      if (maze[i][j] == '.') v.push_back(make_pair(i, j));
    }
  k = v.size() - k;
  dfs(v[0].first, v[0].second);
  for (int i = 0; i < v.size(); i++)
    if (!visited[v[i].first][v[i].second]) maze[v[i].first][v[i].second] = 'X';
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) cout << maze[i][j];
    cout << endl;
  }
  return 0;
}
