Submission #591285

#	Time	Username	Problem	Language	Result	Execution time	Memory
591285		Loki_Nguyen	San (COCI17_san)	C++14	72 / 120	13 ms	2008 KiB

san

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pll pair<ll, int>
#define pii pair<int, int>
#define fi first
#define se second
#define pb push_back

const int N = 3e1 + 3;
const int M = 1 << 20;
const int mod = 1e9 + 7;
const int base = 300;
const ll inf = 1e12;
int pw(int k, int n)
{
    int total = 1;
    for (; n; n >>= 1)
    {
        if (n & 1)
            total = total * k % mod;
        k = k * k % mod;
    }
    return total;
}
int m, n, t, a[N], b[N], c[N], d[N];
vector<int> adj[N], vi;
vector<pll> L, R;
ll ans, tong, k;
struct BIT
{
    int n;
    vector<int> fe;
    BIT(int _n)
    {
        n = _n;
        fe.resize(n + 1, 0);
    }
    void add(int id)
    {
        for (; id <= n; id += id & -id)
            fe[id] += 1;
    }
    int get(int id)
    {
        int res = 0;
        for (; id; id -= id & -id)
            res += fe[id];
        return res;
    }
};
int lwr(int x)
{
    return lower_bound(vi.begin(), vi.end(), x) - vi.begin() + 1;
}
void sol()
{
    cin >> n >> k;
    for (int i = 0; i < n; i++)
    {
        cin >> a[i] >> b[i];
        vi.pb(a[i]);
    }
    BIT bit(n);
    sort(vi.begin(), vi.end());
    vi.erase(unique(vi.begin(), vi.end()), vi.end());
    for (int mask = 1; mask < (1 << (n / 2)); mask++)
    {
        tong = 0;
        int lst = 0;
        for (int i = 0; i < n / 2; i++)
        {
            if (mask >> i & 1)
            {
                if (lst > a[i])
                {
                    tong = -1;
                    break;
                }
                lst = a[i];
                tong += b[i];
            }
        }
        if (tong == -1)
            continue;
        L.pb({tong, lwr(lst)});
        if (tong >= k)
            ++ans;
    }
    for (int mask = 1; mask < (1 << (n - n / 2)); mask++)
    {
        tong = 0;
        int lst = mod;
        for (int i = n - n / 2 - 1; i >= 0; i--)
        {
            if (mask >> i & 1)
            {
                if (lst < a[i + n / 2])
                {
                    tong = -1;
                    break;
                }
                lst = a[i + n / 2];
                tong += b[i + n / 2];
            }
        }
        if (tong == -1)
            continue;
        R.pb({tong, lwr(lst)});
        if (tong >= k)
            ++ans;
    }
    sort(L.begin(), L.end());
    sort(R.begin(), R.end());
    for (pll x : R)
    {
        while (!L.empty() && x.fi + L.back().fi >= k)
        {
            bit.add(L.back().se);
            L.pop_back();
        }
        ans += bit.get(x.se);
    }
    cout << ans;
}
int main()
{
    cin.tie(0);
    cout.tie(0);
    ios_base::sync_with_stdio(0);
#define task "tests"
    if (fopen(task ".inp", "r"))
    {
        freopen(task ".inp", "r", stdin);
        freopen(task ".out", "w", stdout);
    }
    int ntest = 1;
    // cin >> ntest;
    while (ntest-- > 0)
        sol();
}
/*
10 10
259008492 685257993 684081919 849336162 185724174 230558609 147159919 225162936 734023603 130213023
2 1 4
2 4 7
2 2 8
2 4 10
2 5 8
2 5 6
2 1 10
2 3 8
2 1 8
2 2 4
2 1 6
*/

Compilation message (stderr)

san.cpp: In function 'int main()':
san.cpp:134:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  134 |         freopen(task ".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
san.cpp:135:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  135 |         freopen(task ".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 24 / 24
• Subtask 2: 24 / 24
• Subtask 3: 24 / 24
• Subtask 4: 0 / 24
• Subtask 5: 0 / 24