Submission #1273625

#	Time	Username	Problem	Language	Result	Execution time	Memory
1273625		bbldrizzy	Money (IZhO17_money)	C++20	0 / 100	8 ms	16048 KiB

money

#include <bits/stdc++.h>
#include <ios>
#include <iostream>
#include <set>
#include <random>
using namespace std;
using ll = long long;
using P = pair<ll, ll>;
#define f first
#define s second
const int MOD = 1e9+7;
const ll inf = 4*1e18;
const int mx = 5*1e5+5;
int dx[4] = {0, 1, 0, -1};
int dy[4] = {1, 0, -1, 0};
const int N = 1e6+5;

template <class T> class BIT {
  private:
	int size;
	vector<T> bit;
	vector<T> arr;

  public:
	BIT(int size) : size(size), bit(size + 1), arr(size) {}

	/** Sets the value at index ind to val. */
	void set(int ind, T val) { add(ind, val - arr[ind]); }

	/** Adds val to the element at index ind. */
	void add(int ind, T val) {
		arr[ind] += val;
		ind++;
		for (; ind <= size; ind += ind & -ind) { bit[ind] += val; }
	}

	/** @return The sum of all values in [0, ind]. */
	T pref_sum(int ind) {
		ind++;
		T total = 0;
		for (; ind > 0; ind -= ind & -ind) { total += bit[ind]; }
		return total;
	}
};

int main() {
    ios_base::sync_with_stdio(false); cin.tie(nullptr);
    int n; cin >> n;
    BIT<ll> bit(N);
    ll ans = 0;
    ll prev = -1;
    for (int i = 0; i < n; i++) {
        int x; cin >> x;
        if (prev == -1 || x < prev) {
            ans++;
            prev = x;
            // cout << "i: " << i << "\n";
        } else {
            ll v = bit.pref_sum(x-1)-bit.pref_sum(prev);
            // cout << i << ", " <<  bit.pref_sum(x) << " " << bit.pref_sum(prev) << "\n";
            if (v > 0) {
                // cout << "i2: " << i << "\n";
                ans++;
            } 
            prev = x;
        }
        bit.add(x, 1);
    }
    cout << ans << "\n";
}

• Subtask 1: 0 / 9
• Subtask 2: 0 / 16
• Subtask 3: 0 / 20
• Subtask 4: 0 / 55