Submission #143860

#	Time	Username	Problem	Language	Result	Execution time	Memory
143860		daniel920712	Arranging Shoes (IOI19_shoes)	C++14	65 / 100	1071 ms	2680 KiB

shoes

#include <iostream>
#include <stdio.h>
#include <vector>
#include <algorithm>
#include <map>
#include <vector>

using namespace std;

struct A
{
    int l,r;
    int nxl,nxr;
    int how;
}Node[200005];
int a[200005];
int b[200005];
long long count_swaps(std::vector<int> S)
{
    long long ans1=0,small,what,t;
    int i,j,k,N=S.size();
    for(i=0;i<N/2;i++) if(!(S[i]<0&&0-S[i]==S[i+N/2])) break;
    if(i==N/2) return ((long long) N/2)*((long long) N/2-1)/2;
    for(i=0;i<N/2;i++)
    {
        for(j=1;j<=N/2;j++)
        {
            a[j]=100000000;
            b[j]=100000000;
        }
        for(j=2*i;j<N;j++)
        {
            if(S[j]<0) b[0-S[j]]=min(b[0-S[j]],j);
            else a[S[j]]=min(a[S[j]],j);
        }
        small=1000000000;
        for(j=1;j<=N/2;j++)
        {
            t=a[j]+b[j];
            if(a[j]>b[j]) t++;
            if(t<small)
            {
                small=t;
                what=j;
            }
        }
        for(j=2*i;j<N;j++)
        {
            if(S[j]==0-what)
            {
                for(k=j;k>2*i;k--)
                {
                    swap(S[k],S[k-1]);
                    ans1++;
                }
                break;
            }
        }
        for(j=2*i+1;j<N;j++)
        {
            if(S[j]==what)
            {
                for(k=j;k>2*i+1;k--)
                {
                    swap(S[k],S[k-1]);
                    ans1++;
                }
                break;
            }
        }
    }


    return ans1;
}

Compilation message (stderr)

shoes.cpp: In function 'long long int count_swaps(std::vector<int>)':
shoes.cpp:49:23: warning: 'what' may be used uninitialized in this function [-Wmaybe-uninitialized]
             if(S[j]==0-what)
                      ~^~~~~

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