Submission #1012973

#	Time	Username	Problem	Language	Result	Execution time	Memory
1012973		HappyCapybara	Arranging Shoes (IOI19_shoes)	C++17	100 / 100	403 ms	150432 KiB

shoes

#include "shoes.h"
#include<bits/stdc++.h>
using namespace std;
#define ll long long

int n;
vector<int> st;

void tog(int pos, int node=1, int tl=0, int tr=2*n-1){
	if (tl == tr){
		st[node] = 1;
		return;
	}
	int tm = (tl+tr)/2;
	if (pos <= tm) tog(pos, node*2, tl, tm);
	else tog(pos, node*2+1, tm+1, tr);
	st[node] = st[node*2]+st[node*2+1];
}

int query(int l, int r, int node=1, int tl=0, int tr=2*n-1){
	if (l <= tl && tr <= r) return st[node];
	int tm = (tl+tr)/2;
	int res = 0;
	if (l <= tm) res += query(l, r, node*2, tl, tm);
	if (tm+1 <= r) res += query(l, r, node*2+1, tm+1, tr);
	return res;
}

ll count_swaps(vector<int> s){
	n = s.size()/2;
	map<int,queue<int>> m;
	for (int i=0; i<2*n; i++) m[s[i]].push(i);
	ll res = 0;
	vector<bool> done(2*n, false);
	st.resize(8*n, 0);
	for (int i=0; i<2*n; i++){
		if (done[i]) continue;
		int j = m[-s[i]].front();
		m[-s[i]].pop();
		m[s[i]].pop();
		res += j-i;
		res -= query(i, j);
		if (s[i] < 0) res--;
		done[j] = true;
		tog(j);
	}
	return res;
}

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