#include <bits/stdc++.h>
using namespace std;
const int64_t inf = 1e17;
int64_t inp() {
  int64_t x;
  cin >> x;
  return x;
}
string inp_str() {
  string x;
  cin >> x;
  return x;
}
int64_t sqr(int64_t n) { return n * n; }
int64_t power(int64_t a, int64_t b, int64_t mod) {
  int64_t res = 1;
  a %= mod;
  for (int64_t i = (0); i <= (log2(b)); ++i) {
    if (b & (1 << i)) res = (res * a) % mod;
    a = (a * a) % mod;
  }
  return res;
}
int64_t gcd(int64_t a, int64_t b) {
  while (b > 0) {
    int64_t tmp = a % b;
    a = b;
    b = tmp;
  }
  return a;
}
bool is_pal(string s) { return equal((s).begin(), (s).end(), s.rbegin()); }
void fast_io() {
  ios::sync_with_stdio(0);
  cin.tie(0);
}
void file_io(string in, string out) {
  freopen(in.c_str(), "r", stdin);
  freopen(out.c_str(), "w", stdout);
}
void print_bool(bool a) {
  if (a)
    cout << "YES\n";
  else
    cout << "NO\n";
}
int64_t n, k;
string s;
void Input() {
  n = inp(), k = inp();
  s = inp_str();
}
void Solve() {
  vector<vector<int64_t> > res;
  int64_t Max = 0;
  for (int64_t _ = (1); _ <= (n); ++_) {
    bool add = false;
    for (int64_t i = (0); i <= (n - 2); ++i) {
      if (s[i] == 'R' && s[i + 1] == 'L') {
        swap(s[i], s[i + 1]);
        if (!add) res.push_back(vector<int64_t>()), add = true;
        res[res.size() - 1].push_back(i + 1);
        ++i;
        ++Max;
      }
    }
  }
  if (k < res.size() || k > Max)
    cout << -1;
  else {
    int64_t x = k - res.size();
    for (int64_t i = 0; i < res.size(); ++i) {
      int64_t m = res[i].size();
      int64_t j = 0;
      for (j = 0; j < min(x, m - 1); ++j) {
        cout << 1 << " " << res[i][j] << "\n";
      }
      x -= j;
      cout << m - j << " ";
      for (j; j < m; j++) cout << res[i][j] << " ";
      cout << "\n";
    }
  }
}
int main() {
  fast_io();
  Input(), Solve();
  return 0;
}
