[CSES] Two Sets II

void solve()
{
    ll n;
    cin >> n;

    ll s = n * (n + 1);
    s /= 2;

    if (s & 1)
    {
        cout << 0 << "\n";
        return;
    }

    s /= 2;
    vll dp(s + 1, 0LL);
    dp[0] = 1;

    FOR(i, 1, n)
    {
        vll temp = dp;
        FOR(j, 0, s)
        {
            if (j - i >= 0)
            {
                if (j == 8)
                {
                    cerr << j << " " << i << " " << temp[j - i] << "\n";
                }
                dp[j] += temp[j - i];
                dp[j] %= mod;
            }
        }
    }

    debug(dp);

    ll ans = powermod(2, mod - 2, mod);
    ans *= dp[s];
    ans %= mod;

    cout << ans << "\n";
}