#include <bits/stdc++.h>
#define ll long long
#define rep(i,n) for(int i=0;i<(int)n;++i)

using namespace std;

typedef pair<int,int>P;

template<class V> class BIT {
private:
	int n; vector<V> bit;
public:
	void add(int i,V x){ i++; while(i < n) bit[i] += x, i += i & -i;}
	V sum(int i){i++; V s = 0; while(i>0) s += bit[i], i -= i & -i; return s;}
	BIT(int sz){ n = sz + 1, bit.resize(n,0);} //初期値がすべて0の場合
	BIT(vector<V> v){n = (int)v.size()+1; bit.resize(n); rep(i,n) add(i,v[i]);}
	void print(){ rep(i,n-1)cout<<sum(i)-sum(i-1)<< " ";cout<<endl;}
	void print_sum(){ rep(i,n)cout<<sum(i-1)<<" ";cout<<endl;}	//-1スタート
};

int main()
{
    int n;
    scanf("%d",&n);
    vector<int> a(n);
    vector<P> vec(2*n);
    rep(i,n){
        scanf("%d",&a[i]);
        vec[i] = P(a[i],n+i);
    }
    vector<int> l(n),r(n);
    rep(i,n){
        scanf("%d%d",&l[i],&r[i]);
        vec[n+i] = P(a[i]-l[i],i);
    }
    sort(vec.begin(),vec.end());
    BIT<int> bt(n);
    ll ans = 0;
    rep(i,2*n){
        int q = vec[i].second;
        if(q >= n){
            q -= n;
            int id = upper_bound(a.begin(),a.end(),a[q]+r[q]) - a.begin();
            ans += bt.sum(id-1) - bt.sum(q);
        }else{
            bt.add(q,1);
        }
    }
    cout << ans << endl;
    return 0;
}