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#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
int n;
std::vector<std::pair<int, int>> tab;
void add_transition(std::vector<int>& transpoztion, int a, int b) {
    transpoztion.push_back(a);
    transpoztion.push_back(b);
}
std::vector<int> first_transpoztion;
std::vector<int> second_transpoztion;
void calculate_transition(int* permatation) {
    bool* processed = new bool[n];
    for (int i = 0; i < n; processed[i++] = false);
    int* inversed = new int[n];
    for (int i = 0; i < n; inversed[permatation[i]] = i, i++);
    for (int i = 0; i < n; i++) {
        if (processed[i]) continue;
        if (permatation[i] == i) {
            processed[i] = true;
            continue;
        }
        if (permatation[permatation[i]] == i) {
            add_transition(first_transpoztion, i, permatation[i]);
            processed[permatation[i]] = true;
            processed[i] = true;
            continue;
        }
        int position_to_fix = i, where_is_right_person = inversed[i];
        processed[where_is_right_person] = processed[position_to_fix] = true;
        while(true) {
            add_transition(second_transpoztion, position_to_fix, where_is_right_person);
            add_transition(first_transpoztion, position_to_fix, inversed[where_is_right_person]);
            // we want where_is_right_person to be inversed[where_is_right_person]
            where_is_right_person = inversed[where_is_right_person];
            position_to_fix = permatation[position_to_fix];
            processed[where_is_right_person] = processed[position_to_fix] = true;
            if (where_is_right_person == position_to_fix) {
                break;
            }
            if (permatation[position_to_fix] == where_is_right_person) {
                add_transition(second_transpoztion, position_to_fix, where_is_right_person);
                break;
            }
        }
    }
}
void print_transpozition(const std::vector<int>& trans) {
    std::cout << trans.size() << endl;
    for (int i = 0; i < trans.size(); i+=2) std::cout << (trans[i] + 1) << " ";
    for (int i = trans.size() - 1; i > 0; i -= 2) std::cout << (trans[i] + 1) << " ";
    std::cout << endl;
}
int main() {
    std::cin >> n;
    tab.reserve(n);
    int height;
    for (int i = 0; i < n; i++) {
        std::cin >> height;
        tab.push_back({ height, i });
    }
    std::sort(tab.begin(), tab.end());
    int *permatation = new int[n];
    for (int i = 0; i < n; i++) {
        permatation[tab[i].second] = i;    
    }
    calculate_transition(permatation);
    if (first_transpoztion.size() == 0) {
        std::cout << "0\n";
    } else if (second_transpoztion.size() == 0) {
        std::cout << "1\n";
        print_transpozition(first_transpoztion);
    } else {
        std::cout << "2\n";
        print_transpozition(first_transpoztion);
        print_transpozition(second_transpoztion);
    }
}