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#include <cstdio>
#include <algorithm>
#include <vector>
#include <algorithm>
#include <cassert>
#include <cstdlib>

#define MAX 3009
#define DB if(0)
#define PR if(0)
#define RND if (0)

int v[MAX], valToPos[MAX], m[MAX];


void solve(int n, std::vector<int> &r) {
    std::vector<int> in, out;

    int used[n], w[n];
    for (int i=0; i<n; i++) {
        used[i] = 0;
        w[v[i]] = i;
    }

    DB printf("v:\n");
    DB for(int i=0; i<n; i++) printf("%d ", v[i]);
    DB printf("\nwhere:\n");
    DB for(int i=0; i<n; i++) printf("%d ", w[i]);
    DB printf("\n");

    for (int j=0; j<n; j++) {
        int valueToPush = j;
        int whereToPush = j;

        while (valueToPush != v[whereToPush] && !used[valueToPush] && !used[v[whereToPush]]) {
            DB printf("valueToPush: %d, whereToPush: %d, v[whereToPush] = %d, w[valueToPush] = %d\n", valueToPush, whereToPush, v[whereToPush], w[valueToPush]);
            DB printf("swapping positions: %d and %d\n", w[valueToPush], whereToPush);
            in.push_back(w[valueToPush]);
            out.push_back(whereToPush);

            used[v[whereToPush]] = true;
            used[valueToPush] = true;

            valueToPush = w[valueToPush];
            whereToPush = v[whereToPush];

            DB printf("new values value = %d, where = %d\n", valueToPush, whereToPush);
        }
    }

    int cnt = (int)in.size();
    for (int i=0; i<cnt; i++) {
        r.push_back(in[i]);
        std::swap(v[in[i]], v[out[i]]);
    }
    for (int i=cnt-1; i>=0; i--) {
        r.push_back(out[i]);

    }
}

int main() {
//    int sd = 1231;
//    srand(sd);

//    while(true) {
//        for(int i=0; i<MAX; i++) {
//            v[i] = valToPos[i] = m[i] = 0;
//        }
        int n;// = rand() % 300 + 1;
//        if (n % 2) n++;
//        printf("%d\n", n);
    scanf("%d\n", &n);

//        for (int i=0; i<n; i++) v[i] = 1 * (i+1);// + rand() % 10;
//        std::random_shuffle(v, v + n);

        for (int i = 0; i < n; i++) {
//            printf("%d ", v[i]);
            scanf("%d", v + i);
            valToPos[v[i]] = i + 1;
        }
//        printf("\n");

        int cnt = 0;
        for (int i = 0; i < MAX; i++) {
            if (valToPos[i]) m[valToPos[i] - 1] = cnt++;
        }

        for (int i=0; i<n; i++) v[i] = m[i];

        std::vector<int> r1, r2, r3;
        solve(n, r1);
        solve(n, r2);
//        solve(n, r3);

        if (r3.size()) printf("3\n");
        else if (r2.size()) printf("2\n");
        else if (r1.size()) printf("1\n");
        else printf("0\n");

        if (r1.size()) {
            printf("%zu\n", r1.size());
            for (int i = 0; i < r1.size(); i++) {
                printf("%d ", r1[i] + 1);
            }
            printf("\n");
        }

        if (r2.size()) {
            printf("%zu\n", r2.size());
            for (int i = 0; i < r2.size(); i++) {
                printf("%d ", r2[i] + 1);
            }
            printf("\n");
        }

//        if (r3.size()) {
//            printf("%zu\n", r3.size());
//            for (int i = 0; i < r3.size(); i++) {
//                printf("%d ", r3[i] + 1);
//            }
//            printf("\n");
//        }

//        for (int i = 0; i < n - 1; i++) {
//            assert (v[i] < v[i+1]);
//        }
        PR printf("\n-------\n");
//    }
}