Submission #1166548

#	Time	Username	Problem	Language	Result	Execution time	Memory
1166548		monkey133	Exercise Deadlines (CCO20_day1problem2)	C++20	25 / 25	115 ms	14540 KiB

Main

#include <bits/stdc++.h>
//#include "includeall.h"
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
#define endl '\n'
#define f first
#define s second
#define pb push_back
#define mp make_pair
#define lb lower_bound
#define ub upper_bound
#define input(x) scanf("%lld", &x);
#define input2(x, y) scanf("%lld%lld", &x, &y);
#define input3(x, y, z) scanf("%lld%lld%lld", &x, &y, &z);
#define input4(x, y, z, a) scanf("%lld%lld%lld%lld", &x, &y, &z, &a);
#define print(x, y) printf("%lld%c", x, y);
#define show(x) cerr << #x << " is " << x << endl;
#define show2(x,y) cerr << #x << " is " << x << " " << #y << " is " << y << endl;
#define show3(x,y,z) cerr << #x << " is " << x << " " << #y << " is " << y << " " << #z << " is " << z << endl;
#define all(x) x.begin(), x.end()
#define discretize(x) sort(x.begin(), x.end()); x.erase(unique(x.begin(), x.end()), x.end());
#define FOR(i, x, n) for (ll i =x; i<=n; ++i) 
#define RFOR(i, x, n) for (ll i =x; i>=n; --i) 
#pragma GCC optimize("O3","unroll-loops")
using namespace std;
mt19937_64 rnd(chrono::steady_clock::now().time_since_epoch().count());
//using namespace __gnu_pbds;
//#define ordered_set tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update>
//#define ordered_multiset tree<int, null_type, less_equal<int>, rb_tree_tag, tree_order_statistics_node_update>
typedef long long ll;
typedef long double ld;
typedef pair<ld, ll> pd;
typedef pair<string, ll> psl;
typedef pair<ll, ll> pi;
typedef pair<ll, pi> pii;
typedef pair<pi, pi> piii;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());


vector<ll> fenwick(200005,0);

ll ps(ll i)
{
	ll sum=0;
	while (i>0)
	{
		sum+=fenwick[i];
		i-=i&(-i);
	}
	return sum;
}
void update(ll i, ll v)
{
	while (i<200005)
	{
		fenwick[i]+=v;
		i+=i&(-i);
	}
}


int main()
{
	cin.tie(nullptr);
	cout.tie(nullptr);
	ios::sync_with_stdio(false);
	ll n;
	cin >> n;
	vector<ll> v(n), sorted, pos(n);
	set<ll> ss;
	for (ll i=0; i<n; ++i) {cin >> v[i]; ss.insert(i + 1);}
	for (ll i=n-1; i>=0; --i)
	{
		auto it = ss.ub(v[i]);
		if (it==ss.begin()) {cout << -1 << endl; return 0;}
		it--;
		pos[i] = *it;
		ss.erase(it);
	}
	ll ans = 0;
	for (ll i=0; i<n; ++i) 
	{
		ans += i - ps(pos[i]);
		update(pos[i], 1);
	}
	cout << ans << endl;

	return 0;
}

• Subtask 1: 17 / 17
• Subtask 2: 8 / 8