#include <bits/stdc++.h>
using namespace std;
const long long M = 1e9 + 7;
const long long N = 5e5 + 1;
bool prime[N];
void solve() {
  long long n, k;
  cin >> n >> k;
  string s;
  cin >> s;
  vector<vector<long long>> v(k);
  long long cnt = 0, c = 0;
  string t = s;
  bool f = 0;
  while (1) {
    bool b = 0;
    for (long long i = 0; i < n; i++) {
      if (t[i] == 'R' && t[i + 1] == 'L') {
        if (cnt >= k) {
          f = 1;
          break;
        }
        b = 1;
        t[i] = 'L';
        t[i + 1] = 'R';
        i++;
        v[cnt].push_back(i);
        c++;
      }
    }
    if (f) break;
    if (b == 0) break;
    cnt++;
  }
  if (cnt > k || c < k || f) {
    cout << -1 << "\n";
    return;
  } else if (cnt == k) {
    for (auto i : v) {
      cout << i.size() << " ";
      for (auto j : i) cout << j << " ";
      cout << "\n";
    }
  } else {
    long long t = cnt - 1, b = k - 1;
    while (t < b) {
      long long m = v[t].size();
      while (!v[t].empty()) {
        v[b].push_back(v[t].back());
        b--;
        v[t].pop_back();
        if (t >= b) break;
      }
      if (t == b && v[t].size()) break;
      t--;
    }
    for (auto i : v) {
      cout << i.size() << " ";
      for (auto j : i) cout << j << " ";
      cout << "\n";
    }
  }
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int t = 1;
  while (t--) solve();
}
