#include <bits/stdc++.h>   using namespace std;   const int maxn = 2e5 + 5;   int a[maxn], n, s, b[maxn], num[maxn], len;   int ufs[maxn], meme[maxn];   inline int find(int u) {     if (ufs[u] == u)       return u;     else       return ufs[u] = find(ufs[u]);   }   inline void join(int u, int v, int e) {     u = find(u), v = find(v);     if (u == v) return;     ufs[v] = u;     meme[u] = e;   }   vector<vector<int> > mema;   vector<pair<int, int> > adj[maxn];   vector<int> curm;   inline void dfs(int u) {     while (adj[u].size()) {       int v = adj[u].back().first, id = adj[u].back().second;       adj[u].pop_back();       dfs(v);       curm.push_back(id);     }   }   int main() {     cin >> n >> s;     for (int i = 1; i <= n; i++) {       scanf( %d , &a[i]);       num[++len] = a[i];     }     sort(num + 1, num + len + 1);     len = unique(num + 1, num + len + 1) - num - 1;     for (int i = 1; i <= n; i++) {       a[i] = lower_bound(num + 1, num + len + 1, a[i]) - num;       b[i] = a[i];       ufs[i] = i;     }     sort(b + 1, b + n + 1);     int cnt = 0;     for (int i = 1; i <= n; i++) {       if (a[i] != b[i]) {         cnt++;         join(a[i], b[i], i);       }     }     if (cnt > s) {       cout <<  -1  << endl;       return 0;     }     if (cnt == 0) {       cout <<  0  << endl;       return 0;     }     if (s - cnt > 1) {       for (int i = 1; i <= len; i++) {         if (ufs[i] == i && meme[i] != 0) {           curm.push_back(meme[i]);           if (curm.size() == s - cnt) break;         }       }       if (curm.size() > 1) {         mema.push_back(curm);         int lstv = a[curm.back()];         for (int i = curm.size() - 1; i >= 1; i--) {           a[curm[i]] = a[curm[i - 1]];         }         a[curm[0]] = lstv;       }     }     for (int i = 1; i <= n; i++) {       if (a[i] != b[i]) {         adj[a[i]].push_back(make_pair(b[i], i));       }     }     for (int i = 1; i <= len; i++) {       if (adj[i].size() != 0) {         curm.clear();         dfs(i);         mema.push_back(curm);       }     }     cout << mema.size() << endl;     for (int i = 0; i < mema.size(); i++) {       cout << mema[i].size() << endl;       for (int j = 0; j < mema[i].size(); j++) {         printf( %d  , mema[i][j]);       }       cout << endl;     }     return 0;   }   