#include <bits/stdc++.h>
using namespace std;
long long int gcd(long long int a, long long int b) {
  return (!b) ? a : gcd(b, a % b);
}
int n, k;
void solve() {
  cin >> n >> k;
  string s;
  cin >> s;
  vector<vector<int>> mvs;
  int mxs = 0;
  int cnt = 0;
  while (cnt <= n) {
    vector<int> cr;
    for (int i = 0; i <= (int)s.size() - 2; i++) {
      if (s[i] == 'R' && s[i + 1] == 'L') {
        cr.push_back(i);
        s[i] = 'L';
        s[i + 1] = 'R';
        i += 1;
      }
    }
    if ((int)cr.size() == 0) break;
    mvs.push_back(cr);
    mxs += (int)cr.size();
    cnt += 1;
  }
  if (k >= (int)mvs.size() && k <= mxs) {
    int rem = (int)mvs.size();
    for (auto fv : mvs) {
      vector<int> cv = fv;
      int i = 0;
      while (i < (int)cv.size()) {
        int ch = 1;
        if (rem == k) ch = (int)cv.size() - i;
        cout << ch << " ";
        for (int j = 0; j < ch; j++) {
          cout << cv[i] + 1 << " ";
          i += 1;
        }
        cout << '\n';
        k -= 1;
      }
      rem -= 1;
    }
  } else {
    cout << -1;
  }
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  solve();
}
