#include <bits/stdc++.h>
using namespace std;
const int INFint = 2147483647;
const long long INF = 9223372036854775807ll;
const long long MOD = 1000000007ll;
char f[2020][2020];
int n, m;
bool c(int x, int y, int d, int cnt) {
  int cur = 0;
  cerr << x << ' ' << y << endl;
  if (x > 0 && y > 0 && x + d - 1 <= n && y + d - 1 <= m) {
    for (int i = x; i < x + d; i++) {
      cur += (f[i][y] == 'w');
      cur += (f[i][y + d - 1] == 'w');
    }
    for (int i = y + 1; i < y + d - 1; i++) {
      cur += (f[x][i] == 'w');
      cur += (f[x + d - 1][i] == 'w');
    }
    return (cur == cnt);
  }
  return 0;
}
int main() {
  ios_base::sync_with_stdio(0);
  int minx = INFint, miny = INFint, maxx = -INFint, maxy = -INFint;
  cin >> n >> m;
  int cnt = 0;
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= m; j++) {
      cin >> f[i][j];
      if (f[i][j] == 'w') {
        minx = min(minx, i);
        miny = min(miny, j);
        maxx = max(maxx, i);
        maxy = max(maxy, j);
        cnt++;
      }
    }
  }
  int d = max(maxx - minx + 1, maxy - miny + 1);
  cerr << d << endl;
  if (d == 1) {
    for (int it = 1; it <= n; it++) {
      for (int l = 1; l <= m; l++) cout << f[it][l];
      cout << endl;
    }
    return 0;
  }
  int x[3] = {minx, maxx - d + 1, 1};
  int y[3] = {miny, maxy - d + 1, 1};
  for (int i = 0; i < 3; i++) cerr << x[i] << ' ';
  cerr << endl;
  for (int i = 0; i < 3; i++) cerr << y[i] << ' ';
  cerr << endl;
  for (int i = 0; i < 3; i++)
    for (int j = 0; j < 3; j++) {
      if (c(x[i], y[j], d, cnt)) {
        for (int it = x[i]; it < x[i] + d; it++) {
          if (f[it][y[j]] != 'w') f[it][y[j]] = '+';
          if (f[it][y[j] + d - 1] != 'w') f[it][y[j] + d - 1] = '+';
        }
        for (int it = y[j]; it < y[j] + d; it++) {
          if (f[x[i]][it] != 'w') f[x[i]][it] = '+';
          if (f[x[i] + d - 1][it] != 'w') f[x[i] + d - 1][it] = '+';
        }
        for (int it = 1; it <= n; it++) {
          for (int l = 1; l <= m; l++) cout << f[it][l];
          cout << endl;
        }
        return 0;
      }
    }
  cout << -1 << endl;
  fprintf(stderr, "\nTIME = %lf\n", 1.0 * clock() / CLOCKS_PER_SEC);
  return 0;
}
