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#include<bits/stdc++.h>
using namespace std;

int MAX_N = 3000;

struct Node{
    int value;
    int currentIndex;
    int targetIndex;
    bool inCircle;
    bool iterated = false;

    Node(int value, int currentIndex){
        this->value = value;
        this->currentIndex = currentIndex;
        this->inCircle = false;
    }
};

struct CircleGraph{
    Node* fst;
    bool completed = false;
    int iterationIndex = 0;
    int size;

    CircleGraph(Node* fst){
        this->fst = fst;
        this->size = 1;
    }

    CircleGraph(Node* fst, int size){
        this->fst = fst;
        this->size = size;
    }

    Node* next(vector<Node*>& nodes, Node* current=NULL, int step=1){
        if(current==NULL) return fst;
        for(int i=0; i<step; i++){
            current = nodes[current->targetIndex];
        }
        return current;
    }
};

int main(){
    int n; cin >> n;
    vector<Node*> nodes(n);
    map<int ,Node*> input;

    int temp;
    for(int i=0; i<n; i++){
        cin >> temp;
        Node *new_node = new Node(temp, i);
        nodes[i] = new_node;
        input[temp] = new_node;
    }

    int targetIndex = 0;
    for(int x=1; x<=MAX_N; x++){
        auto it = input.find(x);
        if(it != input.end()){
            it->second->targetIndex = targetIndex;
            targetIndex++;            
        }
    }

    vector<CircleGraph*> circles;
    for(auto node: nodes){
        if(!node->inCircle && node->currentIndex != node->targetIndex){
            CircleGraph *newCircle = new CircleGraph(node);
            circles.push_back(newCircle);

            node->inCircle=true;
            auto nextNode = nodes[node->targetIndex];
            while(nextNode != node){
                nextNode->inCircle=true;
                newCircle->size++;
                nextNode = nodes[nextNode->targetIndex];
            }
        }
    }

    bool completed = false;
    vector< vector<int> > results;
    while(!completed){
        completed = true;
        vector<int> selected;
        vector<int> targets;
        for(int i=0; i<circles.size(); i++){
            CircleGraph *circle = circles[i];
            completed &= circle->completed;
            if(!circle->completed){
                Node *first = circle->next(nodes);
                Node *split = circle->next(nodes, first, circle->size/2-1);
                Node *last = circle->next(nodes, split, circle->size-circle->size/2);
                if(last->iterated){
                    first = circle->next(nodes, first);
                    split = circle->next(nodes, split);
                    last = circle->next(nodes, last);
                }
                if(!split->iterated && !last->iterated){
                    selected.push_back(split->currentIndex+1);
                    targets.push_back(last->currentIndex+1);
                    split->iterated = true; last->iterated = true;
                    if(circle->size > 2){
                        Node *nextToSplit = circle->next(nodes, split);
                        CircleGraph *newCircle2 = new CircleGraph(nextToSplit, circle->size/2 + circle->size%2);
                        circles.push_back(newCircle2);
                    }
                    if(circle->size > 3){
                        CircleGraph *newCircle1 = new CircleGraph(first, circle->size/2);
                        circles.push_back(newCircle1);
                    }
                    swap(nodes[split->currentIndex], nodes[last->currentIndex]);
                    swap(split->currentIndex, last->currentIndex);
                    circle->completed = true;
                }
            }
        }
        if(!completed){
            for(int i=targets.size()-1; i>=0; i--){
                selected.push_back(targets[i]);
            }
            results.push_back(selected);
            for(auto x: nodes){
                x->iterated = false;
            }
        }
    }

    cout << results.size() << "\n";
    for(auto& result: results){
        cout << result.size() << "\n";
        for(auto& x: result){
            cout << x << " ";
        }
        cout << "\n";
    }
}