Submission #143899

#	Time	Username	Problem	Language	Result	Execution time	Memory
143899		tincamatei	Arranging Shoes (IOI19_shoes)	C++14	10 / 100	2 ms	380 KiB

shoes

#include "shoes.h"
#include <vector>
#include <cstdlib>

using namespace std;

long long count_swaps(std::vector<int> s) {
	int N = s.size() / 2;
	vector<vector<int> > pozLeft(N), pozRight(N);

	for(int i = 0; i < 2 * N; ++i)
		if(s[i] < 0)
			pozLeft[-s[i] - 1].push_back(i);
		else
			pozRight[s[i] - 1].push_back(i);
	
	long long rez = 0LL;

	for(int i = 0; i < N; ++i) {
		for(int j = 0; j < pozLeft[i].size(); ++j) {
			rez = rez + abs(pozLeft[i][j] - pozRight[i][j]) - 1;
			if(pozLeft[i][j] > pozRight[i][j])
				++rez;
		}
	}

	return rez;
}

Compilation message (stderr)

shoes.cpp: In function 'long long int count_swaps(std::vector<int>)':
shoes.cpp:20:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int j = 0; j < pozLeft[i].size(); ++j) {
                  ~~^~~~~~~~~~~~~~~~~~~

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