Submission #288265

#	Time	Username	Problem	Language	Result	Execution time	Memory
288265		amiratou	Arranging Shoes (IOI19_shoes)	C++14	100 / 100	362 ms	26472 KiB

shoes

#include "shoes.h"
#include <bits/stdc++.h>
#include "ext/pb_ds/assoc_container.hpp"
using namespace std;
using namespace __gnu_pbds;
#define sz(x) (int)(x.size())
#define fi first
#define se second
template<typename T> using ordered_set = tree<T,null_type,less<T>,rb_tree_tag,tree_order_statistics_node_update>;
typedef long long ll;
typedef pair<int,int> ii;
const int MX = (int)(1e5+5);

int n,N;
vector<int> vec[2*MX];

ll count_swaps(vector<int> s) {	
	n=sz(s);
	N=n/2;
	ordered_set <ii> X;
	ll ans=0;
	for (int i = n-1; i >= 0; i--)
	{
		X.insert({i,s[i]});
		if(s[i]>0)vec[s[i]].push_back(i);
		else vec[-s[i]+N].push_back(i);
	}
	while(!X.empty()){
		ii f=(*X.begin()),m;
		if(f.se<0){
			vec[-f.se+N].pop_back();
			m={vec[-f.se].back(),-f.se};
			vec[-f.se].pop_back();
		}
		else{
			vec[f.se].pop_back();
			m={vec[f.se+N].back(),-f.se};
			vec[f.se+N].pop_back();
		}
		ans+=X.order_of_key(m)-1+(f.se>0);
		X.erase(X.begin()),X.erase(m);
	}
	return ans;
}

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