Submission #278486

#	Time	Username	Problem	Language	Result	Execution time	Memory
278486		ctziapo	Arranging Shoes (IOI19_shoes)	C++14	50 / 100	208 ms	44880 KiB

shoes

#include "shoes.h"
#include <cstdio>
#include <cassert>
#include <iostream>
#include <vector>

using namespace std;

int seg[500000];

void update(int s,int e,int u,int ind){

   if(u<s || u>e){
    return;
   }

   if(s==e && s==u){
        seg[ind]=1;
        return;
   }

   int mid=(s+e)/2;
   update(s,mid,u,ind*2);
   update(mid+1,e,u,ind*2+1);

   seg[ind]=seg[ind*2]+seg[ind*2+1];
}

int query(int s,int e , int qs,int qe,int ind){

    if(qs<=s && e<=qe){
        return seg[ind];
    }
    if(qs>e || qe<s){
        return 0;
    }

   int mid=(s+e)/2;
   int p1=query(s,mid,qs,qe,ind*2);
   int p2=query(mid+1,e,qs,qe,ind*2+1);

   return p1+p2;

}
long long count_swaps(std::vector<int> s) {

    vector < int > row;
    vector < int > row2;
    vector < vector < int > > l(s.size()+1,row);
    vector < vector < int > > r(s.size()+1,row2);

    int li[s.size()+1]={};
    int ri[s.size()+1]={};

    for(int i=0;i<s.size();i++){
        if(s[i]>0){
            r[s[i]].push_back(i);
        }
        else
            l[-s[i]].push_back(i);
    }

	int ans=0;

	/// n log n
    int v[s.size()]={};
	for(int i=0;i<s.size();i++){
        int cou=0;
        if(v[i]==1){
            continue;
        }

        int f=-s[i];
        if(f>0){
        li[f]++;
        int start=i;
        int e=r[f][ri[f]];
        ri[f]++;
        int q=query(1,s.size(),start+1,e+1,1);

        v[start]=1;
        v[e]=1;

        update(1,s.size(),start+1,1);
        update(1,s.size(),e+1,1);
       // cout<<q<<endl;
        cou=cou + e-start-1-q;
        }
        else{
            cou=1;
             ri[-f]++;
             int start=i;
             int e=l[-f][li[-f]];
             li[-f]++;

            int q=query(1,s.size(),start+1,e+1,1);

             v[start]=1;
        v[e]=1;

        update(1,s.size(),start+1,1);
        update(1,s.size(),e+1,1);
         //   cout<<q<<endl;
             cou=cou + e-start-1-q;
        }
        ans+=cou;
	}

	return ans;

	  /*
	/// n^2
	int v[s.size()]={};
	for(int i=0;i<s.size();i++){
            if(v[i]==1)
                continue;
            int cou=0;
            if(s[i]>0)
                cou=1;
            int f=-s[i];
        for(int j=i+1;j<s.size();j++){
            if(s[j]==f && v[j]!=1){
                v[j]=1;
                v[i]=1;
               //  cout<<cou<<" "<<i<<" "<<j<<endl;
                break;

            }
            if(v[j]==0){
                cou++;
            }
        }

        ans+=cou;
	}
	*/

}

Compilation message (stderr)

shoes.cpp: In function 'long long int count_swaps(std::vector<int>)':
shoes.cpp:55:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   55 |     for(int i=0;i<s.size();i++){
      |                 ~^~~~~~~~~
shoes.cpp:67:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   67 |  for(int i=0;i<s.size();i++){
      |              ~^~~~~~~~~

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