Submission #823025

#	Time	Username	Problem	Language	Result	Execution time	Memory
823025		vjudge1	Arranging Shoes (IOI19_shoes)	C++17	50 / 100	15 ms	1848 KiB

shoes

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

long long count_swaps(vector<int> s) {
	long long ans = 0, x = 0, n = s.size(), sum = 0;
	if (n <= 2000){
		while (s.size() > 0){
			for (int j = 1 ; j < s.size() ; j++){
				if (s[0] * -1 == s[j]){
					ans+=j - 1;
					if (s[0] > 0)
						ans++;
					//cout << 0 << " " << j << '\n';
					s.erase(s.begin() + j, s.begin() + j + 1);
					s.erase(s.begin() + 0, s.begin() + 0 + 1);
					break ;
				}
			}
		}
		return ans;
	}
	else{
		return (n/2) * ((n/2) + 1)/2;
	}
}

Compilation message (stderr)

shoes.cpp: In function 'long long int count_swaps(std::vector<int>)':
shoes.cpp:9:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    9 |    for (int j = 1 ; j < s.size() ; j++){
      |                     ~~^~~~~~~~~~
shoes.cpp:6:21: warning: unused variable 'x' [-Wunused-variable]
    6 |  long long ans = 0, x = 0, n = s.size(), sum = 0;
      |                     ^
shoes.cpp:6:42: warning: unused variable 'sum' [-Wunused-variable]
    6 |  long long ans = 0, x = 0, n = s.size(), sum = 0;
      |                                          ^~~

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