/*input
*/
#include <bits/stdc++.h>
#pragma GCC optimize("unroll-loops,no-stack-protector")
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef pair<ld,ld> pdd;
#define IOS ios_base::sync_with_stdio(0); cin.tie(0)
#define ALL(a) a.begin(),a.end()
#define SZ(a) ((int)a.size())
#define F first
#define S second
#define REP(i,n) for(int i=0;i<((int)n);i++)
#define eb emplace_back
#define pb push_back
#define MP(a,b) make_pair(a,b)
#define SORT_UNIQUE(c) (sort(c.begin(),c.end()), c.resize(distance(c.begin(),unique(c.begin(),c.end()))))
#define GET_POS(c,x) (lower_bound(c.begin(),c.end(),x)-c.begin())
#define EL cout<<'\n'
template<typename T1,typename T2>
ostream& operator<<(ostream& out,pair<T1,T2> P){
out<<'('<<P.F<<','<<P.S<<')';
return out;
}
template<typename T>
ostream& operator<<(ostream& out,vector<T> V){
REP(i,SZ(V)) out<<V[i]<<((i!=SZ(V)-1)?" ":"");
return out;
}
#define version 20190814
//}}}
const ll maxn=100005;
const ll maxlg=20;
const ll INF64=1e18;
const int INF=0x3f3f3f3f;
const ll MOD=ll(1e9+7);
const ld PI=acos(-1);
const ld eps=1e-9;
//const ll p=880301;
//const ll P=31;
ll mypow(ll a,ll b){
ll res=1LL;
while(b){
if(b&1) res=res*a%MOD;
a=a*a%MOD;
b>>=1;
}
return res;
}
int n;
vector<pii> p;
vector<int> sz[maxn+maxn];
int pt[maxn+maxn];
int BIT[maxn+maxn];
int low(int i){
return i&-i;
}
void mdf(int n,int d){
for(int i=n;i<maxn+maxn;i+=low(i+1)){
BIT[i]+=d;
}
}
int query(int n){
int ret=0;
for(int i=n;i>=0;i-=low(i+1)){
ret+=BIT[i];
}
return ret;
}
int query(int l,int r){
return query(r-1)-query(l-1);
}
ll count_swaps(vector<int> a){
ll ans=0;
n=SZ(a)/2;
REP(i,n+n){
int cur=a[i];
if(pt[-cur+maxn]==SZ(sz[-cur+maxn])){
sz[cur+maxn].pb(i);
}
else{
p.eb(sz[maxn-cur][pt[maxn-cur]],i);
if(cur<0) ans++;
pt[maxn-cur]++;
}
}
sort(ALL(p));
for(auto i:p){
ans+=2*(query(i.S,n+2))+query(i.F,i.S);
mdf(i.S,1);
}
return ans;
}
int main(){
cout<<count_swaps(vector<int>{-1,1,-1,1})<<'\n';
}
Compilation message
/tmp/ccSMfJW3.o: In function `main':
grader.cpp:(.text.startup+0x0): multiple definition of `main'
/tmp/ccnWoAJJ.o:shoes.cpp:(.text.startup+0x0): first defined here
collect2: error: ld returned 1 exit status
