#include <bits/stdc++.h>
#define pb push_back
#define eb emplace_back
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define uniq(x) x.erase(unique(all(x)), x.end())
#define rall(x) x.rbegin(), x.rend()
//#define int long long
using namespace std;
using ll = long long;
using ull = unsigned long long;
using ld = long double;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
const int mod = 1e9 + 7;
const int LOG = 20;
const int maxn = 1e5 + 5;
const double eps = 1e-9;
void setIO() {
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
}
struct SegTree {
int n;
vector<int> tree;
SegTree(int n) : n(n), tree(4*n+5, 0) {}
void update(int u, int tl, int tr, int pos, int val) {
if(tl == tr) {
tree[u] += val;
} else {
int tm = (tl + tr) / 2;
if(pos <= tm)
update(2*u, tl, tm, pos, val);
else
update(2*u+1, tm+1, tr, pos, val);
tree[u] = tree[2*u] + tree[2*u+1];
}
}
int query(int u, int tl, int tr, int l, int r) {
if(tl > tr || l > tr || tl > r) return 0;
if(l <= tl && tr <= r) return tree[u];
int tm = (tl + tr) / 2;
return query(2*u, tl, tm, l, r)
+ query(2*u+1, tm+1, tr, l, r);
}
void update(int pos, int val) {
update(1, 0, n-1, pos, val);
}
int query(int l, int r) {
return query(1, 0, n-1, l, r);
}
};
int64_t count_swaps(vector<int> S) {
int n = sz(S) / 2;
set<int> diff;
for(int &x : S) diff.insert(abs(x));
ll ans = 0;
map<int, vector<int> > occ;
map<int, int> ptr;
vector<bool> vis(2*n, false);
SegTree tree(2*n);
for(int i=0; i<2*n; i++) {
occ[S[i]].push_back(i);
if(!ptr.count(S[i])) ptr[S[i]] = 0;
}
for(int i=0; i<2*n; i++) {
if(vis[i]) continue;
vis[i] = true;
int to_pair_pos = occ[-S[i]][ptr[-S[i]]];
cout << i+1 << " " << to_pair_pos+1 << '\n';
vis[to_pair_pos] = true;
if(S[i] < 0) {
ans += (to_pair_pos - i - 1);
} else {
ans += (to_pair_pos - i);
}
ans -= tree.query(i, to_pair_pos);
tree.update(to_pair_pos, 1);
ptr[-S[i]]++;
ptr[S[i]]++;
}
return ans;
}
// int32_t main() {
// setIO();
// int n;
// cin >> n;
// vector<int> v(2*n);
// for(int &x : v) cin >> x;
// cout << count_swaps(v) << '\n';
// return 0;
// }
