# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
332366 | nicholask | Arranging Shoes (IOI19_shoes) | C++14 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
//#include "shoes.h"
#include <bits/stdc++.h>
using namespace std;
long long count_swaps(vector <int> s){
int n=(s.size()>>1);
if (n<=1000){
long long ans=0;
for (int i=0; i<n+n; i+=2){
int wh;
for (int j=1; ; j++){
if (s[0]*-1==s[j]){
wh=j;
break;
}
}
if (s[0]>0) ans++;
ans+=wh-1;
s.erase(s.begin()+wh);
s.erase(s.begin());
}
return ans;
} else {
return n*1ll*(n-1);
}
}
signed main(){
int n;
cin>>n;
vector <int> v(n);
for (int i=0; i<n; i++) cin>>v[i];
cout<<count_swaps(v);
}