Submission #677055

#	Time	Username	Problem	Language	Result	Execution time	Memory
677055		hello_there_123	Arranging Shoes (IOI19_shoes)	C++17	100 / 100	525 ms	148824 KiB

shoes

#include<bits/stdc++.h>
#include "shoes.h"
using namespace std;
#define ll long long 
ll n;
ll ft[200005];
inline ll ls(int x){return x & -x; }
ll qry(ll p){
	p++;
	if(p<1) return 0;
	ll r = 0;
	for(;p;p-=ls(p)) r+=ft[p];
	return r;
}
void upd(ll p, ll v){
	p++;
	for(;p<=n;p+=ls(p)) ft[p]+=v;
}
long long count_swaps(vector<int>s) {
    ll ans = 0;
	n = s.size(); 
	map<ll,queue<ll> >mp;
	for(ll i=0;i<n;i++){
		ll x = s[i];
		mp[x].push(i);
	}
	bool arr[n+3];
	memset(arr,0,sizeof(arr));
	for(ll i=0;i<n;i++){
		if(arr[i]) continue;
		mp[s[i]].pop();
		ll first = mp[-s[i]].front();
		mp[-s[i]].pop();
		ans+=first-i-1-(qry(first)-qry(i-1));
		upd(first,1);
		arr[first] = 1;
		if(s[i]>0) ans++;
	}
	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