Submission #474197

#	Time	Username	Problem	Language	Result	Execution time	Memory
474197		jwvg0425	Sorting (IOI15_sorting)	C++17	20 / 100	106 ms	592 KiB

sorting

#include <stdio.h>
#include <vector>
#include <queue>
#include <algorithm>
#include <iostream>
#include <string>
#include <bitset>
#include <map>
#include <set>
#include <tuple>
#include <string.h>
#include <math.h>
#include <random>
#include <functional>
#include <assert.h>
#include <math.h>
#include "sorting.h"
#define all(x) (x).begin(), (x).end()
#define xx first
#define yy second

using namespace std;

template<typename T, typename Pr = less<T>>
using pq = priority_queue<T, vector<T>, Pr>;
using i64 = long long int;
using ii = pair<int, int>;
using ii64 = pair<i64, i64>;

bool sorted(vector<int> s)
{
	for (int i = 0; i < s.size(); i++)
		if (s[i] != i)
			return false;

	return true;
}

vector<ii> solve(vector<int> s, vector<ii> r)
{
	int n = s.size();
	int m = r.size();
	vector<ii> res;

	for (int i = 0; i < m && !sorted(s); i++)
	{
		vector<int> rev(n), idx(n);
		swap(s[r[i].xx], s[r[i].yy]);
		for (int j = 0; j < n; j++)
			rev[j] = j;

		for (int j = i + 1; j < m; j++)
			swap(rev[r[j].xx], rev[r[j].yy]);

		for (int j = 0; j < n; j++)
			idx[rev[j]] = j;

		// s[i] -> idx[i]
		bool f = false;
		for (int x = 0; x < n; x++)
		{
			if (s[x] == idx[x])
				continue;

			int j = find(all(s), idx[x]) - s.begin();

			res.emplace_back(x, j);
			swap(s[x], s[j]);
			f = true;
			break;
		}

		if (!f)
			res.emplace_back(0, 0);
	}

	if (!sorted(s))
	{
		int* p = nullptr;
		*p = 0xDEADBEFF;
	}

	return res;
}

int findSwapPairs(int N, int S[], int M, int X[], int Y[], int P[], int Q[])
{
	vector<int> s(N);
	vector<ii> r(M);

	for (int i = 0; i < N; i++)
		s[i] = S[i];

	for (int i = 0; i < M; i++)
	{
		r[i].xx = X[i];
		r[i].yy = Y[i];
	}

	auto res = solve(s, r);

	for (int i = 0; i < res.size(); i++)
	{
		P[i] = res[i].xx;
		Q[i] = res[i].yy;
	}

	return res.size();
}

Compilation message (stderr)

sorting.cpp: In function 'bool sorted(std::vector<int>)':
sorting.cpp:32:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   32 |  for (int i = 0; i < s.size(); i++)
      |                  ~~^~~~~~~~~~
sorting.cpp: In function 'std::vector<std::pair<int, int> > solve(std::vector<int>, std::vector<std::pair<int, int> >)':
sorting.cpp:41:16: warning: conversion from 'std::vector<int>::size_type' {aka 'long unsigned int'} to 'int' may change value [-Wconversion]
   41 |  int n = s.size();
      |          ~~~~~~^~
sorting.cpp:42:16: warning: conversion from 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} to 'int' may change value [-Wconversion]
   42 |  int m = r.size();
      |          ~~~~~~^~
sorting.cpp:65:33: warning: conversion from '__gnu_cxx::__normal_iterator<int*, std::vector<int> >::difference_type' {aka 'long int'} to 'int' may change value [-Wconversion]
   65 |    int j = find(all(s), idx[x]) - s.begin();
      |            ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~
sorting.cpp: In function 'int findSwapPairs(int, int*, int, int*, int*, int*, int*)':
sorting.cpp:102:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  102 |  for (int i = 0; i < res.size(); i++)
      |                  ~~^~~~~~~~~~~~
sorting.cpp:108:17: warning: conversion from 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} to 'int' may change value [-Wconversion]
  108 |  return res.size();
      |         ~~~~~~~~^~

• Subtask 1: 8 / 8
• Subtask 2: 12 / 12
• Subtask 3: 0 / 16
• Subtask 4: 0 / 18
• Subtask 5: 0 / 20
• Subtask 6: 0 / 26