Submission #771251

#	Time	Username	Problem	Language	Result	Execution time	Memory
771251		teamariaa	Arranging Shoes (IOI19_shoes)	C++17	45 / 100	18 ms	3152 KiB

shoes

#include <bits/stdc++.h>
#include "shoes.h"

using namespace std;

long long count_swaps(vector<int> s)
{
    long long n = s.size() / 2;
    if(n == 1)
        if(s[0] < s[1])
            return 0;
        else
            return 1;

    bool ok = 0;
    for(int i = 1; i < s.size()  &&  !ok; i ++)
        if(abs(s[i]) != abs(s[i - 1]))
          ok = 1;

    if(!ok)
    {
        int pos = 0;
        long long ans = 0;
        for(int i = 0; i < s.size(); i ++)
            if(s[i] < 0)
            {
                ans += abs(i - pos);
                pos += 2;
            }
        return ans;
    }

    return n * (n - 1) / 2;
}

Compilation message (stderr)

shoes.cpp: In function 'long long int count_swaps(std::vector<int>)':
shoes.cpp:9:7: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
    9 |     if(n == 1)
      |       ^
shoes.cpp:16:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   16 |     for(int i = 1; i < s.size()  &&  !ok; i ++)
      |                    ~~^~~~~~~~~~
shoes.cpp:24:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   24 |         for(int i = 0; i < s.size(); i ++)
      |                        ~~^~~~~~~~~~

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