# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
1110785 | epicci23 | Arranging Shoes (IOI19_shoes) | C++17 | 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 "bits/stdc++.h"
using namespace std;
//#define int long long
#define all(x) (x).begin(),(x).end()
#define sz(x) (int)x.size()
struct Fenwick{
vector<int64_t> fw;
int N;
Fenwick(int64_t _n){
N = _n + 15;
fw.assign(N,0);
}
void upd(int64_t c){
for(;c<N;c+=c&-c) fw[c]++;
}
int64_t query(int64_t c,int64_t res=0){
for(;c;c-=c&-c) res+=fw[c];
return res;
}
};
int64_t count_swaps(vector<int> S){
int64_t n , ans = 0;
n = sz(S) / 2;
int64_t ar[2 * n + 5];
for(int i=1;i<=2*n;i++) ar[i] = S[i - 1];
if(n<=8){
vector<int64_t> xd;
for(int i=1;i<=2*n;i++) if(ar[i]<0) xd.push_back(ar[i]);
sort(all(xd));
int64_t res = (int)1e9;
do{
int hm = 0, p = 1;
queue<int64_t> q1[n+5];
queue<int64_t> q2[n+5];
for(int i=1;i<=2*n;i++){
if(ar[i]<0) q1[-ar[i]].push(i);
else q2[ar[i]].push(i);
}
Fenwick F(2*n);
for(int u:xd){
int64_t c = q1[u].front();
q1[u].pop();
int64_t x = q2[u].front();
q1[u].pop();
F.upd(c);
c+=F.query(2*n)-F.query(c);
hm+=c-p;
p++;
F.upd(x);
x+=F.query(2*n)-F.query(x);
hm+=x-p;
p++;
}
res=min(res,hm);
}while(all(xd));
return res;
}
/*int p = 1;
while(!q.empty()){
int64_t c = q.front();
q.pop();
int64_t x = pos[-ar[c]].back();
pos[-ar[c]].pop_back();
F.upd(c);
c+=F.query(2*n)-F.query(c);
ans+=c-p;
p++;
F.upd(x);
x+=F.query(2*n)-F.query(x);
ans+=x-p;
p++;
}
return ans;*/
}
/*void _(){
int n,ans=0; cin >> n;
int ar[2*n+5];
for(int i=1;i<=2*n;i++) cin >> ar[i];
queue<int> q;
vector<int> pos[n+5];
Fenwick F(2*n);
for(int i=1;i<=2*n;i++){
if(ar[i]<0) q.push(i);
else pos[ar[i]].push_back(i);
}
for(int i=1;i<=n;i++) reverse(all(pos[i]));
int p = 1;
while(!q.empty()){
int64_t c = q.front();
q.pop();
int64_t x = pos[-ar[c]].back();
pos[-ar[c]].pop_back();
F.upd(c);
c+=F.query(2*n)-F.query(c);
ans+=c-p;
p++;
F.upd(x);
x+=F.query(2*n)-F.query(x);
ans+=x-p;
p++;
}
cout << ans << '\n';
}
int32_t main(){
ios::sync_with_stdio(0);
cin.tie(0);
int tc=1;//cin >> tc;
while(tc--) _();
}*/