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#include <iostream>
#include <vector>
#include <algorithm>
#include <map>
#include <unordered_set>

using namespace std;

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    int n;
    cin >> n;

    map<int,int> SA = {};
    vector<int> S(n);

    for(int i = 0; i < n; i++) {
        cin >> S[i];
        SA[S[i]] = i;
    }

    vector<int> SS(S);
    sort(SS.begin(), SS.end());

    map<int, map<int,bool>> SM = {};

    vector<int> SC(S);

    map<int, unordered_set<int>> SZ = {};

    int oz = 0;

    for(int i = 0; i < n; i++) {
        int ia = SA[SS[i]];

        if(SC[ia] == SC[i]) {
            continue;
        }

        if(SM.find(i-1) != SM.end()) {
            SZ[oz].insert(i);
            SZ[oz].insert(ia);
        }else oz++;

        SM[i][ia] = true;

        swap(SC[i], SC[ia]);
        swap(SA[SC[i]], SA[SC[ia]]);
    }

    for(int i = 0; i <= oz; i++) {
        if(SZ.find(i) == SZ.end()){
            continue;
        }

        auto szs = SZ[i];
        if(szs.size() == 0){
            cerr << "0-sized\n";
            continue;
        }

        cout << szs.size() << "\n";
        for(auto j = szs.begin(); j != szs.end(); j++) {
            cout << *j << " ";
        }
        cout << "\n";
    }
}