Submission #297347

#	Time	Username	Problem	Language	Result	Execution time	Memory
297347		Saboon	Arranging Shoes (IOI19_shoes)	C++17	50 / 100	1064 ms	27356 KiB

shoes

#include "shoes.h"
#include <bits/stdc++.h>
using namespace std;
map<int,set<int>> S;

long long count_swaps(vector<int> a){
	int n = (int)a.size() / 2;
	long long ret = 0;
	for (int now = 0; now < 2*n; now += 2){
		vector<pair<int,int>> Joft;
		for (int i = 0; i < a.size(); i++){
			int x = a[i];
			if (!S[-x].empty()){
				Joft.push_back({*S[-x].begin(),i});
				S[-x].erase(S[-x].begin());
			}
			else
				S[x].insert(i);
		}
		auto it = *min_element(Joft.begin(), Joft.end());
		int v = it.first, u = it.second;
		if (a[v] > a[u])
			ret ++;
		ret += v+u-1;
		a.erase(a.begin()+u);
		a.erase(a.begin()+v);
	}
	return ret;
}

Compilation message (stderr)

shoes.cpp: In function 'long long int count_swaps(std::vector<int>)':
shoes.cpp:11:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   11 |   for (int i = 0; i < a.size(); i++){
      |                   ~~^~~~~~~~~~

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