Submission #403167

#	Time	Username	Problem	Language	Result	Execution time	Memory
403167		SavicS	Arranging Shoes (IOI19_shoes)	C++14	100 / 100	154 ms	33656 KiB

shoes

#include "shoes.h"

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <bits/stdc++.h>

#define fi first
#define se second
#define pb push_back
#define sz(a) (int)a.size()
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define ff(i,a,b) for(int i=a;i<=b;i++)
#define fb(i,b,a) for(int i=b;i>=a;i--)

using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef pair<int,int> pii;
const int maxn = 200005;
const int inf = 1e9 + 5;

template<typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

// os.order_of_key(k) the number of elements in the os less than k
// *os.find_by_order(k)  print the k-th smallest number in os(0-based)

int n;
int niz[maxn];

set<int> poz[maxn];
set<int> neg[maxn];

ll dud[maxn];
void upd(int x, ll val){
	while(x <= maxn){
		dud[x] += val;
		x += x&(-x);
	}
}

ll query(int x){
	ll sum = 0;
	while(x > 0){
		sum += dud[x];
		 x -= x&(-x);
	}
	return sum;
}
 
ll count_swaps(vector<int> S){
	n = sz(S);
	ff(i,0,n - 1)niz[i + 1] = S[i];
	
	ff(i,1,n){
		if(niz[i] < 0)neg[-niz[i]].insert(i);
		else poz[niz[i]].insert(i);
		upd(i, 1);
	}
	
	ll rez = 0;
	ff(i,1,n){
		int X = niz[i];
		
		if(X < 0 && neg[-X].count(i) == 0)continue;
		if(X > 0 && poz[X].count(i) == 0)continue;
		
		if(X < 0){
			auto a = poz[-X].begin();
			poz[-X].erase(a), neg[-X].erase(i);

			rez += query(*a) - query(i) - 1;
			upd(i, 1), upd(*a + 1, -1);
						
		}
		else{
			auto a = neg[X].begin();
			neg[X].erase(a), poz[X].erase(i);
			
			rez += query(*a) - query(i);
			upd(i, 1), upd(*a + 1, -1);			
			
		}
		
		
	}
	
	return rez;
		
				
}

//int main()
//{
//    ios::sync_with_stdio(false);
//    cout.tie(nullptr);
//    cin.tie(nullptr);
//	cin >> n;
//	vector<int> a(n);
//	ff(i,0,n - 1)cin >> a[i];
//	
//	cout << count_swaps(a) << endl;
//	
//    return 0;
//}
/**

4
2 1 -1 -2

6
-2 2 2 -2 -2 2

4
-2 -1 2 1

// probati bojenje sahovski ili slicno

**/

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 20 / 20
• Subtask 4: 15 / 15
• Subtask 5: 20 / 20
• Subtask 6: 15 / 15