#include <bits/stdc++.h>
using namespace std;
int tag[505][505];
char maze[505][505];
int dot, n, m, k;
int bfs(int u, int v) {
  queue<int> Q;
  Q.push(u);
  Q.push(v);
  tag[u][v] = 1;
  int count = 1;
  while (!Q.empty() && count < dot - k) {
    int a = Q.front();
    Q.pop();
    int b = Q.front();
    Q.pop();
    if (a + 1 < n && !tag[a + 1][b] && maze[a + 1][b] == '.') {
      Q.push(a + 1);
      Q.push(b);
      tag[a + 1][b] = 1;
      count++;
      if (count == dot - k) break;
    }
    if (a - 1 >= 0 && !tag[a - 1][b] && maze[a - 1][b] == '.') {
      Q.push(a - 1);
      Q.push(b);
      tag[a - 1][b] = 1;
      count++;
      if (count == dot - k) break;
    }
    if (b + 1 < m && !tag[a][b + 1] && maze[a][b + 1] == '.') {
      Q.push(a);
      Q.push(b + 1);
      tag[a][b + 1] = 1;
      count++;
      if (count == dot - k) break;
    }
    if (b - 1 >= 0 && !tag[a][b - 1] && maze[a][b - 1] == '.') {
      Q.push(a);
      Q.push(b - 1);
      tag[a][b - 1] = 1;
      count++;
      if (count == dot - k) break;
    }
  }
  if (count < dot - k) memset(tag, 0, sizeof tag);
  return count;
}
int main() {
  scanf("%d%d%d", &n, &m, &k);
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) cin >> maze[i][j];
  }
  dot = 0;
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      if (maze[i][j] == '.') dot++;
    }
  }
  int x;
  memset(tag, 0, sizeof tag);
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      if (maze[i][j] == '.' && !tag[i][j]) {
        x = bfs(i, j);
      }
      if (x == dot - k) break;
    }
    if (x == dot - k) break;
  }
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < m; j++) {
      if (tag[i][j] == 0 && maze[i][j] == '.')
        printf("X");
      else
        printf("%c", maze[i][j]);
    }
    printf("\n");
  }
  return 0;
}
