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#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;
/*
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 * */



struct Person {
    int height;
    int startIndex;
    int targetIndex;
    bool processed;
};

bool person_sorter(Person const &lp, Person const &rp) {
    return lp.height < rp.height;
}

bool canBeSolvedInOneRound(int n, Person *initPersons) {
    for (int i = 0; i < n; i++) {
        if (initPersons[initPersons[i].targetIndex].targetIndex != i) {
            return false;
        }
    }
    return true;
}

void solveInitialRound(int n, Person *persons, vector<int> &a, vector<int> &b) {
    for (int i = 0; i < n; i++) {
        int index1 = i;
        int index2 = persons[persons[i].targetIndex].targetIndex;  //whaaaat?

        if (persons[i].targetIndex != persons[i].startIndex
            && !persons[index1].processed
            && !persons[index2].processed
            && index2 != i) {

            a.push_back(index1);
            b.push_back(index2);

            persons[index1].processed = true;
            persons[index2].processed = true;

            Person p1 = persons[index1];
            Person p2 = persons[index2];
            persons[index1] = p2;
            persons[index2] = p1;
            persons[index1].startIndex = index1;
            persons[index2].startIndex = index2;
        }
    }

    for (int i = 0; i < n; i++) {
        persons[i].processed = false;
    }
}

void printResults(vector<vector<int> > vec2) {
    for(int v = 0; v < vec2.size(); v+=2) {
        vector<int> a = vec2[v];
        vector<int> b = vec2[v+1];
        printf("%lu\n", a.size() * 2);
        for (int i = 0; i < a.size(); i++) {
            printf("%d ", a[i] + 1);
        }
        for (int i = b.size() - 1; i >= 0; i--) {
            printf("%d ", b[i] + 1);
        }
        printf("\n");
    }
}

void solveFinalRound(int n, Person *persons) {
    vector<int> a;
    vector<int> b;
    for (int i = 0; i < n; i++) {
        if (persons[i].targetIndex != persons[i].startIndex
            && !persons[i].processed
            && !persons[persons[i].targetIndex].processed) {
            //TODO check second processed flag

            a.push_back(persons[i].targetIndex);
            b.push_back(persons[i].startIndex);
            persons[i].processed = true;
            persons[persons[i].targetIndex].processed = true;
        }
    }
//    reverse(b.begin(), b.end());
    printf("%lu\n", a.size() * 2);
    for (int i = 0; i < a.size(); i++) {
        printf("%d ", a[i] + 1);
    }
    for (int i = b.size() - 1; i >= 0; i--) {
        printf("%d ", b[i] + 1);
    }
    printf("\n");
}

int main() {
    int n, h;
    scanf("%d", &n);
    Person persons[n];
    Person initPositionsPersons[n];
    for (int i = 0; i < n; i++) {
        scanf("%d", &h);
        persons[i].height = h;
        persons[i].startIndex = i;
        initPositionsPersons[i].height = h;
        initPositionsPersons[i].startIndex = i;
        initPositionsPersons[i].processed = false;
    }
    std::sort(persons, persons + n, person_sorter);
    bool isSorted = true;
    for (int i = 0; i < n; i++) {
        persons[i].targetIndex = i;
        initPositionsPersons[persons[i].startIndex].targetIndex = i;
        if (persons[i].startIndex != persons[i].targetIndex) {
            isSorted = false;
        }
    }
    if (isSorted) {
        ::printf("0\n");
        return 0;
    }
    int rounds = 1;
    vector<vector<int> > vec2;
    while (!canBeSolvedInOneRound(n, initPositionsPersons)) {
        vector<int> a;
        vector<int> b;
        solveInitialRound(n, initPositionsPersons, a, b);
        rounds++;
        vec2.push_back(a);
        vec2.push_back(b);
    }
    printf("%d\n", rounds);
    printResults(vec2);
    solveFinalRound(n, initPositionsPersons);
    return 0;
}