#include <iostream>
#include <cstdio>
#include <stdio.h>
#include <cstdlib>
#include <cmath>
#include <memory.h>
#include <string>
#include <algorithm>
#include <vector>
#include <queue>
#include <map>
#include <set>

using namespace std;

#define ll long long

FILE *fin = freopen("skyscraper.in", "r", stdin);
FILE *fout = freopen("skyscraper.out", "w", stdout);

vector<int> memo[1 << 18];
pair<ll, int> masks[1 << 18];
ll c[18];
int n;
ll w;

void get(int mask)
{
    ll total = 0;
    for (int i = 0; i < n; i++)
        if (mask & (1 << i))
        {
            memo[mask].push_back(i);
            total += c[i];
        }
    masks[mask] = make_pair(total, mask);
}

int main()
{
    scanf("%d%lld", &n, &w);
    for (int i = 0; i < n; i++)
        scanf("%lld", c+i);
    for (int mask = 0; mask < (1 << n); mask++)
        get(mask);
    sort(masks + 1, masks + (1 << n));
    reverse(masks + 1, masks + (1 << n));
    int mask = 0;
    vector<int> ans;
    for (int i = 1; i < (1 << n); i++)
    {
        if (!(masks[i].second & mask) && masks[i].first <= w)
        {
            ans.push_back(masks[i].second);
            mask |= masks[i].second;
        }
    }
    printf("%d\n", ans.size());
    for (int i = 0; i < ans.size(); i++)
    {
        printf("%d", memo[ans[i]].size());
        for (int j = 0; j < memo[ans[i]].size(); j++)
            printf(" %d", memo[ans[i]][j]+1);
        puts("");
    }
    return 0;
}