This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
#define ll long long
#define MAXN 50
using namespace std;
ll a[MAXN];
set<ll> s1,s2;
map<ll,ll> cnt1,cnt2;
void Solve(ll l,ll r,ll cur,ll pos,set<ll> &s,map<ll,ll> &cnt)
{
    if (pos>r)
    {
        s.insert(cur);
        cnt[cur]++;
        return;
    }
    Solve(l,r,cur,pos+1,s,cnt);
    Solve(l,r,cur+a[pos],pos+1,s,cnt);
}
int main()
{
    ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    ll n,m,ans=0;
    cin >> n >> m;
    for (ll i=1;i<=n;i++)
        cin >> a[i];
    Solve(1,n/2,0,1,s1,cnt1);
    Solve(n/2+1,n,0,n/2+1,s2,cnt2);
    ll cur=0;
    for (auto i : s2)
    {
        cur+=cnt2[i];
        cnt2[i]=cur;
    }
    for (auto i : s1)
    {
        auto it=s2.lower_bound(m-i);
        if ((*it)!=m-i)
        {
            if (it==s2.begin())
                continue;
            it--;
        }
        ans+=cnt1[i]*cnt2[*it];
    }
    cout << ans;
    return 0;
}
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