input()
a=sorted(map(abs,map(int,input().split())))
r=i=j=0
while i<len(a):
while 2*a[j]<a[i]:j+=1
r+=i-j;i+=1
print(r)#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define fi first
#define se second
#define sst string
#define pb push_back
#define maxco 100000+5
#define lld long double
#define cha ios_base::sync_with_stdio(false);
#define ffl cout.flush();
#define phi acos(-1)
#define mod 1000000000
#define mp make_pair
#define pqpair priority_queue<pair<ll,ll> ,vector<pair<ll,ll>>,greater<pair<ll,ll>>>
pqpair pq;
#define INF 1000000000
#define MAXN 100009
#define pi pair<ll,ll>
ll n,m,k,s;
ll a[200009];
vector<ll> vec[100009];
ll vis[100009];
bool cur[100009];
int main(){
cha
ll n;
cin>>n;
for(ll i=1;i<=n;i++){
cin>>a[i];
a[i]=abs(a[i]);
}
sort(a+1,a+n+1);
ll ans=0;
for(ll i=1;i<n;i++){
ll lb=lower_bound(a+1, a+n+1, 2*a[i]+1)-a;
if(lb==n+1){
lb--;
}
while(a[lb]>2*a[i]){
lb--;
}
ans+=lb-i;
}
cout<<ans;
}
780C - Andryusha and Colored Balloons | 1153A - Serval and Bus |
1487C - Minimum Ties | 1136A - Nastya Is Reading a Book |
1353B - Two Arrays And Swaps | 1490E - Accidental Victory |
1335A - Candies and Two Sisters | 96B - Lucky Numbers (easy) |
1151B - Dima and a Bad XOR | 1435B - A New Technique |
1633A - Div 7 | 268A - Games |
1062B - Math | 1294C - Product of Three Numbers |
749A - Bachgold Problem | 1486B - Eastern Exhibition |
1363A - Odd Selection | 131B - Opposites Attract |
490C - Hacking Cypher | 158B - Taxi |
41C - Email address | 1373D - Maximum Sum on Even Positions |
1574C - Slay the Dragon | 621A - Wet Shark and Odd and Even |
1395A - Boboniu Likes to Color Balls | 1637C - Andrew and Stones |
1334B - Middle Class | 260C - Balls and Boxes |
1554A - Cherry | 11B - Jumping Jack |