Submission #312795

#	Time	Username	Problem	Language	Result	Execution time	Memory
312795		Basilhijaz	Arranging Shoes (IOI19_shoes)	C++17	50 / 100	1136 ms	541936 KiB

shoes

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

using namespace std;

#define pb push_back

vector<pair<int, int> > pairs;
long long count_swaps(vector<int> s) {
    int n = s.size();
    queue<int> left[2*n + 1];
    queue<int> right[2*n + 1];
    bool done[n];
    memset(done, 0, sizeof(done));
    /*for(int i = 0; i < n; i++){
        if(s[i] < 0){
            if(!right[abs(s[i])].empty()){
                pairs.pb({right[abs(s[i])].top(), i});
                right[abs(s[i])].pop();
            }
            else{
                left[abs(s[i])].push(i);
            }
        }
        else{
            if(!left[s[i]].empty()){
                pairs.pb({left[s[i]].top(), i});
                left[s[i]].pop();
            }
            else{
                right[s[i]].push(i);
            }
        }
    }
    /**/
    for(int i = 0; i < n; i++){
        if(!done[i]){
            int serach = s[i]*-1;
            int first = -1; int second = -1;
            first = i;
            for(int j = i + 1; j < n; j++){
                if(s[j] == serach && !done[j]){
                    second = j;
                    done[j] = 1;
                    break;
                }
            }
            pairs.pb({first, second});
        }
    }
    int ans = 0;
    for(int i = 0; i < pairs.size(); i++){
        if(s[pairs[i].first] > 0){
            ans++;
        }
    }
    memset(done, 0, sizeof(done));
    for(int i = 0; i < pairs.size(); i++){
        done[pairs[i].second] = 1;
        for(int j = pairs[i].first + 1; j < pairs[i].second; j++){
            if(!done[j])ans++;
        }
    }
	return ans;
}

Compilation message (stderr)

shoes.cpp:35:5: warning: "/*" within comment [-Wcomment]
   35 |     /**/
      |      
shoes.cpp: In function 'long long int count_swaps(std::vector<int>)':
shoes.cpp:52:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   52 |     for(int i = 0; i < pairs.size(); i++){
      |                    ~~^~~~~~~~~~~~~~
shoes.cpp:58:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   58 |     for(int i = 0; i < pairs.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