#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using vi = vector<int>;
using pi = pair<int, int>;
const int mod = 1e9 + 7;
const ll inf = ll(1e18);
const double PI = acos(-1), eps = 1e-9;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const int mxn = 2e5 + 5, mxa = 1e3, mxk = 5;
const int dx[] = {1, 0, -1, 0, 1, 1, -1, -1},
          dy[] = {0, 1, 0, -1, -1, 1, -1, 1};
int n, k;
int getmx(vi &a) {
  int res = 0, pos = 0;
  for (int i = 0; i < (int)(a).size(); ++i) {
    if (a[i] == 0) {
      res += i - pos;
      ++pos;
    }
  }
  return res;
}
void solve() {
  cin >> n >> k;
  vi a(n), dp(n);
  for (int i = 0; i < n; ++i) {
    char c;
    cin >> c;
    a[i] = (c == 'L' ? 0 : 1);
  }
  int mn = 0;
  for (int i = 0, pre = -1, pos = 0; i < n; ++i) {
    if (a[i] == 0) {
      if (pre != -1) dp[i] = dp[pre] + 1;
      dp[i] = max(dp[i], i - pos);
      pre = i;
      ++pos;
      mn = dp[i];
    }
  }
  if (k < mn || k > getmx(a)) {
    cout << "-1\n";
    return;
  }
  vector<vi> ans;
  while (k) {
    vi change;
    for (int i = 0; i + 1 < n; ++i) {
      if (a[i] == 1 && a[i + 1] == 0) change.push_back(i);
    }
    for (const int x : change) swap(a[x], a[x + 1]);
    --k;
    if (k <= getmx(a)) {
      ans.push_back(change);
      continue;
    }
    ++k;
    for (const int x : change) swap(a[x], a[x + 1]);
    change.clear();
    int need = getmx(a) - k + 1;
    for (int i = 0; i + 1 < n && need > 0; ++i) {
      if (a[i] == 1 && a[i + 1] == 0) {
        change.push_back(i);
        --need;
      }
    }
    for (const int x : change) swap(a[x], a[x + 1]);
    ans.push_back(change);
    --k;
    break;
  }
  int start = 0;
  while (start < n && (a[start] == 1 || start - 1 < 0 || a[start - 1] == 0))
    ++start;
  int pos = 0;
  while (pos < n && a[pos] == 0) ++pos;
  while (start < n) {
    for (int i = start - 1; i >= pos; --i) ans.push_back({i});
    ++pos;
    ++start;
    while (start < n && a[start] == 1) ++start;
  }
  for (const vi &v : ans) {
    cout << (int)(v).size() << ' ';
    for (const int x : v) cout << x + 1 << ' ';
    cout << '\n';
  }
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  int T = 1;
  for (int tt = 1; tt <= T; ++tt) {
    solve();
  }
}
