#include<bits/stdc++.h>
using namespace std;
using ll=long long;
using ld=long double;
using P=pair<ll,ll>;
#define MOD 1000000007ll
#define INF 1000000000ll
#define EPS 1e-10
#define FOR(i,n,m) for(ll i=n;i<(ll)m;i++)
#define REP(i,n) FOR(i,0,n)
#define DUMP(a) REP(d,a.size()){cout<<a[d];if(d!=a.size()-1)cout<<" ";else cout<<endl;}
#define ALL(v) v.begin(),v.end()
#define UNIQUE(v) sort(ALL(v));v.erase(unique(ALL(v)),v.end());
#define pb push_back

ll N = 300030;
ll bit[300030];
void add(ll a, ll w) {
	a++;
	for (ll x = a; x <= N; x += x & -x) bit[x] += w;
}
ll sum(ll a) {
	a++;
	ll ret = 0;
	for (ll x = a; x > 0; x -= x & -x) ret += bit[x];
	return ret;
}
void init() {
	for(ll i=0; i < N; i++) bit[i] = 0;
}

int main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	ll n;
	cin>>n;
	vector<ll> a(n);
	REP(i,n) cin>>a[i];
	vector<ll> l(n);
	vector<ll> r(n);
	REP(i,n) cin>>l[i]>>r[i];
	ll ans=0;
	vector<ll> b(n);
	priority_queue<P,vector<P>,greater<P>> q;
	REP(i,n) {
		while(!q.empty()&&(q.top()).first<a[i]) {
			add((q.top()).second,-1);
			q.pop();
		}
		auto ite=lower_bound(ALL(a),a[i]-l[i]);
		ans+=sum(i);
		if(ite!=a.begin()) ans-=sum((ite-a.begin())-1);
		add(i,1);
		q.push(P(a[i]+r[i],i));
	}
	cout<<ans<<endl;
}