Submission #1033751

#	Time	Username	Problem	Language	Result	Execution time	Memory
1033751		ender	Arranging Shoes (IOI19_shoes)	C++17	85 / 100	40 ms	4432 KiB

shoes

#include "shoes.h"
#include <bits/stdc++.h>
 
using namespace std;
 
long long count_swaps(std::vector<int> s) {
 
	if(s.size() > 2000){
 
		long long ans = 0;
	int cl = 0, cr = 0;
	priority_queue<int, vector<int>, greater<int>> l, r;
 
	for(int i = 0; i < s.size(); ++i){
 
		if(s[i] < 0) l.push(i);
		else r.push(i);
 
	}
 
	for(int i = 0; i < s.size(); ++i){
 
		if(i%2 == 0){
 
			if(s[i] > 0){
				
				ans += l.top() - i;
				swap(s[i], s[l.top()]);
				r.pop();
				r.push(l.top());
			} 
 
			l.pop();
 
		}else {
 
			if(s[i] < 0){
 
				ans += r.top() - i;
				swap(s[i], s[r.top()]);	
				l.pop();
				l.push(r.top());
			} 
			
			r.pop();
 
		}
 
	}
 
	return ans;
 
 
	}
 
	long long ans = 0;
 
	for(int i = 0; i < s.size(); i += 2){
 
		if(s[i] < 0){ 
 
			for(int j = i+1; j < s.size(); ++j){
 
				if(s[j] == -s[i]){
 
					for(int k = j; k > i+1; --k){
 
						swap(s[k], s[k-1]);
						ans++;
 
					}
 
					break;
 
				}
 
			}
 
		}else { 
 
			int target = -s[i];
 
			for(int j = i+1; j < s.size(); ++j){
 
				if(s[j] == target){
 
					for(int k = j; k > i; --k){
 
						swap(s[k], s[k-1]);
						ans++;
 
					}
 
					break;
 
				}
 
			}
 
 
		}
 
	}
	return ans;
}

Compilation message (stderr)

shoes.cpp: In function 'long long int count_swaps(std::vector<int>)':
shoes.cpp:14:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   14 |  for(int i = 0; i < s.size(); ++i){
      |                 ~~^~~~~~~~~~
shoes.cpp:21:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   21 |  for(int i = 0; i < s.size(); ++i){
      |                 ~~^~~~~~~~~~
shoes.cpp:11:6: warning: unused variable 'cl' [-Wunused-variable]
   11 |  int cl = 0, cr = 0;
      |      ^~
shoes.cpp:11:14: warning: unused variable 'cr' [-Wunused-variable]
   11 |  int cl = 0, cr = 0;
      |              ^~
shoes.cpp:58:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   58 |  for(int i = 0; i < s.size(); i += 2){
      |                 ~~^~~~~~~~~~
shoes.cpp:62:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   62 |    for(int j = i+1; j < s.size(); ++j){
      |                     ~~^~~~~~~~~~
shoes.cpp:83:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   83 |    for(int j = i+1; j < s.size(); ++j){
      |                     ~~^~~~~~~~~~

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