#include <bits/stdc++.h>
using namespace std;
vector<vector<bool>> vis;
vector<vector<char>> grid;
void fastIO() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
}
long long operation(long long a, long long b, char op) {
  if (op == '|') return a | b;
  return a ^ b;
}
int n, m, k, cnt = 0, tot = 0;
void display(vector<vector<char>> &v) {
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      cout << grid[i][j];
    }
    cout << "\n";
  }
}
void dfs(int i, int j) {
  if (cnt == tot - k) return;
  vis[i][j] = true;
  cnt++;
  vector<pair<int, int>> neigh;
  if (i + 1 < n && grid[i + 1][j] == '.')
    neigh.push_back(pair<int, int>(i + 1, j));
  if (j + 1 < m && grid[i][j + 1] == '.')
    neigh.push_back(pair<int, int>(i, j + 1));
  if (i - 1 >= 0 && grid[i - 1][j] == '.')
    neigh.push_back(pair<int, int>(i - 1, j));
  if (j - 1 >= 0 && grid[i][j - 1] == '.')
    neigh.push_back(pair<int, int>(i, j - 1));
  for (auto pr : neigh) {
    if (vis[pr.first][pr.second]) continue;
    dfs(pr.first, pr.second);
  }
}
void solve() {
  cin >> n >> m >> k;
  grid = vector<vector<char>>(n, vector<char>(m));
  vis = vector<vector<bool>>(n, vector<bool>(m, false));
  for (int i = 0; i < n; i++) {
    string line;
    cin >> line;
    for (int j = 0; j < m; j++) {
      grid[i][j] = line[j];
      if (line[j] == '.') tot++;
    }
  }
  cnt = 0;
  int si, sj;
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      if (grid[i][j] == '.') {
        si = i, sj = j;
        break;
      }
    }
  }
  dfs(si, sj);
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      if (grid[i][j] == '.' && vis[i][j] == false) grid[i][j] = 'X';
    }
  }
  display(grid);
}
int main() {
  solve();
  return 0;
}
