#include <bits/stdc++.h>
using namespace std;
using ll = long long;
char a[501][501];
bool visited[501][501];
int co = 0;
int s = 0;
int n, m, k;
void dfs(int i, int j) {
  if (visited[i][j]) return;
  if (co == s - k) return;
  co++;
  visited[i][j] = true;
  vector<pair<int, int>> vec;
  if (j - 1 > 0 && a[i][j - 1] == '.') {
    dfs(i, j - 1);
  }
  if (j + 1 <= m && a[i][j + 1] == '.') {
    dfs(i, j + 1);
  }
  if (i - 1 > 0 && a[i - 1][j] == '.') {
    dfs(i - 1, j);
  }
  if (i + 1 <= n && a[i + 1][j] == '.') {
    dfs(i + 1, j);
  }
  return;
}
int main() {
  cin >> n >> m >> k;
  int x, y;
  for (int i = 1; i <= n; i++) {
    string str;
    cin >> str;
    for (int j = 1; j <= m; j++) {
      visited[i][j] = false;
      a[i][j] = str[j - 1];
      if (a[i][j] == '.') {
        x = i;
        y = j;
        s++;
      }
    }
  }
  dfs(x, y);
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= m; j++) {
      if (a[i][j] == '.' && !visited[i][j])
        cout << 'X';
      else
        cout << a[i][j];
    }
    cout << endl;
  }
}
