#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using db = double;
using ld = long double;
template <typename T>
using V = vector<T>;
template <typename T>
using VV = vector<vector<T>>;
constexpr ll mod = 1000000007;
constexpr ll INF = 1000000099;
constexpr ll LINF = (ll)(1e18 + 99);
const vector<ll> dx = {-1, 1, 0, 0}, dy = {0, 0, -1, 1};
template <typename T, typename U>
inline bool chmin(T& t, const U& u) {
  if (t > u) {
    t = u;
    return 1;
  }
  return 0;
}
template <typename T, typename U>
inline bool chmax(T& t, const U& u) {
  if (t < u) {
    t = u;
    return 1;
  }
  return 0;
}
template <typename T>
inline T gcd(T a, T b) {
  return b ? gcd(b, a % b) : a;
}
template <typename T, typename Y>
inline T mpow(T a, Y n) {
  T res = 1;
  for (; n; n >>= 1) {
    if (n & 1) res = res * a;
    a = a * a;
  }
  return res;
}
signed main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  cout << fixed << setprecision(20);
  int n, k;
  cin >> n >> k;
  VV<int> ans(k, V<int>(0));
  V<int> v(n);
  string s;
  cin >> s;
  ll rcnt = 0;
  ll ire = k - 1, das = -1;
  for (ll i = 0; i < (ll)(n); ++i) {
    if (s[i] == 'R') {
      rcnt++;
      v[i] = 1;
    } else {
      v[i] = 0;
    }
  }
  for (ll i = 0; i < (ll)(k); ++i) {
    for (ll j = 0; j < (ll)(n - 1); ++j) {
      if (v[j] == 1 && v[j + 1] == 0) {
        swap(v[j], v[j + 1]);
        ans[i].push_back(j);
        das = i;
        j++;
      }
    }
    if (ans[i].empty()) break;
    reverse((ans[i]).begin(), (ans[i]).end());
  }
  for (ll i = n - rcnt; i < (ll)(n); ++i) {
    if (0 == v[i]) {
      cout << -1 << '\n';
      return 0;
    }
  }
  if ((ll)(ans[k - 1]).size() == 0) {
    while (1) {
      if (das == -1 || das == ire) break;
      ans[ire].push_back(ans[das].back());
      ans[das].pop_back();
      if (ans[das].empty()) das--;
      ire--;
    }
  }
  if (ans[ire].empty()) {
    cout << -1 << '\n';
  } else {
    for (ll i = 0; i < (ll)(k); ++i) {
      cout << (ll)(ans[i]).size() << " ";
      for (ll j = 0; j < (ll)((ll)(ans[i]).size() - 1); ++j) {
        cout << ans[i][j] + 1 << " ";
      }
      cout << ans[i].back() + 1 << '\n';
    }
  }
}
