#include <bits/stdc++.h>
using namespace std;
template <typename T>
inline T GCD(T a, T b) {
  a = abs(a);
  b = abs(b);
  while (b) {
    a = a % b;
    swap(a, b);
  }
  return a;
}
template <typename T>
inline T LCM(T x, T y) {
  T tp = GCD(x, y);
  if ((x / tp) * 1. * y > 9e18) return 9e18;
  return (x / tp) * y;
}
template <typename T>
inline T BigMod(T A, T B, T M) {
  T ret = 1;
  while (B) {
    if (B & 1) ret = (ret * A) % M;
    A = (A * A) % M;
    B = B >> 1;
  }
  return ret;
}
template <typename T>
inline T InvMod(T A, T M) {
  return BigMod(A, M - 2, M);
}
long long gcdr(long long a, long long b) {
  if (a == 0) return b;
  return gcdr(b % a, a);
}
long long max(long long a, long long b) {
  if (a > b) return a;
  return b;
}
long long min(long long a, long long b) {
  if (a < b) return a;
  return b;
}
void FastIO() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.precision(20);
}
char arr[550][550];
long long n, m, k;
long long findd = 0;
long long dx[] = {0, 0, 1, -1};
long long dy[] = {1, -1, 0, 0};
long long visited[550][550] = {0};
long long node, comp = 0;
bool dfs(long long nodex, long long nodey) {
  long long add = 1;
  node++;
  long long ans = false;
  visited[nodex][nodey] = 1;
  if (node == findd) {
    comp = 1;
    return true;
  }
  long long i, j;
  for (i = 0; i < 4 && !comp; i++) {
    long long u = nodex + dx[i];
    long long v = nodey + dy[i];
    if (u < n && u >= 0 && v < m && v >= 0) {
      if (arr[u][v] == '.' && visited[u][v] == 0) {
        ans = ans | dfs(u, v);
      }
    }
  }
  return ans;
}
int main() {
  long long t, i, j, x, y;
  t = 1;
  while (t--) {
    scanf("%lld", &n);
    scanf("%lld %lld", &m, &k);
    for (i = 0; i < n; i++) {
      cin >> arr[i];
    }
    long long emptyy = 0;
    long long lasti, lastj;
    for (i = 0; i < n; i++) {
      for (j = 0; j < m; j++) {
        if (arr[i][j] == '.') {
          emptyy++;
          lasti = i;
          lastj = j;
        }
      }
    }
    findd = emptyy - k;
    dfs(lasti, lastj);
    for (i = 0; i < n; i++) {
      for (j = 0; j < m; j++) {
        if (visited[i][j] == 0 && arr[i][j] == '.') {
          cout << 'X';
        } else
          cout << arr[i][j];
      }
      cout << endl;
    }
  }
  return 0;
}
