제출 #494943

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
494943		luka1234	Arranging Shoes (IOI19_shoes)	C++14	100 / 100	79 ms	13472 KiB

shoes

#include "shoes.h"
#include<bits/stdc++.h>
#define ll long long
#define ff first
#define ss second
using namespace std;
int maxn=200001;
ll f[200001];
int getsum(int v){
    int ans=0;
    for(int i=v;i>=1;i=(i&(i-1))){
        ans+=f[i];
    }
    return ans;
}
void update(int v,int x){
	for(int i=v;i<=maxn;i=2*i-(i&(i-1))){
        f[i]+=x;
    }
}
long long count_swaps(std::vector<int> s) {
	int n=s.size()/2;
	ll ans=0;
	vector<pair<int,int>> v;
	vector<pair<int,int>> inde[maxn];
	for(int i=0;i<(int)s.size();i++){
		inde[abs(s[i])].push_back({s[i],i});
	}
	for(int i=1;i<=n;i++){
		sort(inde[i].begin(),inde[i].end());
		for(int j=0;j<((int)inde[i].size()/2);j++){
			int l=inde[i][j].ss;
			int r=inde[i][j+((int)inde[i].size()/2)].ss;
			if(l>r){
				swap(l,r);
				ans++;
			}
			v.push_back({l+1,r+1});
		}
	}
	for(int i=1;i<=2*n;i++) 
	   update(i,1);
	sort(v.begin(),v.end());
	for(pair<int,int> i:v){
		ans+=getsum(i.ss-1)-getsum(i.ff);
		update(i.ff,-1);
		update(i.ss,-1);
	}
	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