#include <bits/stdc++.h>
using namespace std;
int N, M, K;
char m[500][501];
int dx[4] = {1, -1, 0, 0}, dy[4] = {0, 0, 1, -1};
int main() {
  scanf("%d%d%d", &N, &M, &K);
  for (int(i) = 0; (i) < (N); (i)++) scanf("%s", &m[i]);
  int sx = 0, sy = 0, s = 0;
  for (int(i) = 0; (i) < (N); (i)++)
    for (int(j) = 0; (j) < (M); (j)++)
      if (m[i][j] == '.') s++, sx = i, sy = j;
  queue<pair<int, int> > q;
  q.push(make_pair(sx, sy));
  m[sx][sy] = 'X';
  int sz = 1;
  while (!q.empty()) {
    int x = q.front().first, y = q.front().second;
    q.pop();
    if (sz == s - K) break;
    for (int(d) = 0; (d) < (4); (d)++) {
      int nx = x + dx[d], ny = y + dy[d];
      if (0 <= nx && nx < N && 0 <= ny && ny < M && m[nx][ny] == '.') {
        sz++;
        m[nx][ny] = 'X';
        if (sz == s - K) goto out;
        q.push(make_pair(nx, ny));
      }
    }
  }
out:;
  for (int(i) = 0; (i) < (N); (i)++) {
    for (int(j) = 0; (j) < (M); (j)++) {
      if (m[i][j] == 'X')
        putchar('.');
      else if (m[i][j] == '.')
        putchar('X');
      else
        putchar(m[i][j]);
    }
    puts("");
  }
}
