Submission #736669

#	Time	Username	Problem	Language	Result	Execution time	Memory
736669		bobthebuilder	Arranging Shoes (IOI19_shoes)	C++17	45 / 100	38 ms	11212 KiB

shoes

#include "shoes.h"
#include<bits/stdc++.h>
using namespace std;
#define sz(x) (int)x.size()
#define REP(i,n) for(int i=0;i<n;i++)
#define REP1(i,n) for(int i=1;i<=n;i++)
#define pb push_back
#define lowb(x) (x&(-x))
#define ALL(x) x.begin(),x.end()
const int maxn=2e5+5;
int pos[maxn];
#define ll long long
vector<int> v[maxn];
int bit[maxn];
void upd(int x,int v){
	while(x<maxn){
		bit[x]+=v;
		x+=lowb(x);
	}
}
int query(int x){
	int ans=0;
	while(x){
		ans+=bit[x];
		x-=lowb(x);
	}
	return ans;
}
long long count_swaps(std::vector<int> s) {
	int n=sz(s)/2;
	int cur=0;
	REP(i,2*n){
		if(s[i]<0){
			pos[i]=2*cur;
			v[-s[i]].pb(cur);
			++cur;
		}
	}
	REP1(i,n) reverse(ALL(v[i]));
	REP(i,2*n){
		if(s[i]>0){
			pos[i]=2*v[s[i]].back()+1;
			v[s[i]].pop_back();
		}
	}
	ll ans=0;
	REP(i,2*n){
		ans+=i-query(pos[i]);
		upd(pos[i]+1,1);
	}
	return ans;
}

• Subtask 1: 10 / 10
• Subtask 2: 0 / 20
• Subtask 3: 20 / 20
• Subtask 4: 15 / 15
• Subtask 5: 0 / 20
• Subtask 6: 0 / 15