Submission #543183

#	Time	Username	Problem	Language	Result	Execution time	Memory
543183		SmolBrain	San (COCI17_san)	C++17	120 / 120	471 ms	19012 KiB

san

// Om Namah Shivaya
// GM in 126 days

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;

template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

typedef long long int ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define endl '\n'
#define pb push_back
#define conts continue
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "YES" << endl
#define no cout << "NO" << endl
#define ff first
#define ss second
#define ceil2(x,y) ((x+y-1) / (y))
#define sz(a) a.size()
#define setbits(x) __builtin_popcountll(x)
#ifndef ONLINE_JUDGE
#define debug(x) cout << #x <<" = "; print(x); cout << endl
#else
#define debug(x)
#endif

#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)

bool iseven(ll n) {if ((n & 1) == 0) return true; return false;}

void print(ll t) {cout << t;}
void print(int t) {cout << t;}
void print(string t) {cout << t;}
void print(char t) {cout << t;}
void print(double t) {cout << t;}
void print(ld t) {cout << t;}

template <class T, class V> void print(pair <T, V> p);
template <class T> void print(vector <T> v);
template <class T> void print(set <T> v);
template <class T, class V> void print(map <T, V> v);
template <class T> void print(multiset <T> v);
template <class T, class V> void print(pair <T, V> p) {cout << "{"; print(p.ff); cout << ","; print(p.ss); cout << "}";}
template <class T> void print(vector <T> v) {cout << "[ "; for (T i : v) {print(i); cout << " ";} cout << "]";}
template <class T> void print(set <T> v) {cout << "[ "; for (T i : v) {print(i); cout << " ";} cout << "]";}
template <class T> void print(multiset <T> v) {cout << "[ "; for (T i : v) {print(i); cout << " ";} cout << "]";}
template <class T, class V> void print(map <T, V> v) {cout << "[ "; for (auto i : v) {print(i); cout << " ";} cout << "]";}
template<typename T> void amin(T &a, T b) { a = min(a, b); }
template<typename T> void amax(T &a, T b) { a = max(a, b); }

void usaco(string filename) {
    freopen((filename + ".in").c_str(), "r", stdin);
    freopen((filename + ".out").c_str(), "w", stdout);
}

const int MOD = 1e9 + 7;
const int maxn = 1e5 + 5;
const int inf1 = 1e9 + 5;
const ll inf2 = ll(1e18) + 5;

template<typename T>
struct fenwick {
    int siz;
    vector<T> tree;

    fenwick(int n) {
        siz = n;
        tree = vector<T>(n + 1);
    }

    int lsb(int x) {
        return __builtin_ffs(x) - 1;
    }

    void build(vector<T> &a, int n) {
        for (int i = 1; i <= n; ++i) {
            int toadd = 1 << lsb(i);
            int par = i + toadd;
            tree[i] += a[i];

            if (par <= siz) {
                tree[par] += tree[i];
            }
        }
    }

    void pupd(int i, T v) {
        while (i <= siz) {
            tree[i] += v;
            int toadd = 1 << lsb(i);
            i += toadd;
        }
    }

    T sum(int i) {
        T res = 0;

        while (i) {
            res += tree[i];
            int tosub = 1 << lsb(i);
            i -= tosub;
        }

        return res;
    }

    T query(int l, int r) {
        T res = sum(r) - sum(l - 1);
        return res;
    }
};


void solve(int test_case)
{
    ll n, k; cin >> n >> k;
    vector<pll> a(n);
    rep(i, n) cin >> a[i].ff >> a[i].ss;

    vector<ll> b(n);
    rep(i, n) b[i] = a[i].ff;

    sort(all(b));
    auto it = unique(all(b));
    b.resize(it - b.begin());

    rep(i, n) a[i].ff = lower_bound(all(b), a[i].ff) - b.begin();

    b.clear();

    ll group1 = n / 2, group2 = ceil2(n, 2);
    vector<vector<ll>> val1(n), val2(n);

    rep(mask, 1 << group1) {
        ll prev = 0, sum = 0;
        bool flag = true;

        rep(i, group1) {
            ll f = 1ll << i;
            if (!(mask & f)) conts;

            if (a[i].ff < prev) {
                flag = false;
                break;
            }

            prev = a[i].ff;
            sum += a[i].ss;
        }

        if (!flag) conts;

        val1[prev].pb(sum);
        b.pb(k - sum);
    }

    rep(mask, 1 << group2) {
        ll prev = 0, sum = 0;
        bool flag = true;

        rep(i, group2) {
            ll f = 1ll << i;
            if (!(mask & f)) conts;

            if (a[i + group1].ff < prev) {
                flag = false;
                break;
            }

            prev = a[i + group1].ff;
            sum += a[i + group1].ss;
        }

        if (!flag) conts;

        ll first = n - 1;
        rep(i, group2) {
            ll f = 1 << i;
            if (mask & f) {
                first = a[i + group1].ff;
                break;
            }
        }

        val2[first].pb(sum);
        b.pb(sum);
    }

    sort(all(b));
    auto it2 = unique(all(b));
    b.resize(it2 - b.begin());

    ll siz = sz(b);
    fenwick<ll> fenw(siz + 5);

    Tree<pll> os;
    ll ans = 0;
    ll cnt = 0;

    rev(i, n - 1, 0) {
        trav(x, val2[i]) {
            ll val = lower_bound(all(b), x) - b.begin() + 1;
            fenw.pupd(val, 1);
        }

        trav(x, val1[i]) {
            ll mn = k - x;
            ll val = lower_bound(all(b), mn) - b.begin() + 1;
            ans += fenw.query(val, siz);
        }
    }

    cout << ans << endl;
}

int main()
{
    fastio;

    int t = 1;
    // cin >> t;
    rep1(i, t) {
        solve(i);
    }

    return 0;
}

Compilation message (stderr)

san.cpp: In function 'void solve(int)':
san.cpp:210:8: warning: unused variable 'cnt' [-Wunused-variable]
  210 |     ll cnt = 0;
      |        ^~~
san.cpp: In function 'void usaco(std::string)':
san.cpp:64:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   64 |     freopen((filename + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
san.cpp:65:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   65 |     freopen((filename + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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