#include<string>
#include<algorithm>
#pragma GCC optimize("O3")
#pragma GCC target("avx")
#define ll long long

using namespace std;

struct P {
    int x, y;
    P(){}
    P(int a, int b) : x(a), y(b){}
    bool operator< (const P& a) const {
        return (this->x == a.x)?(this->y < a.y):(this->x < a.x);
    }
};

#define getchar getchar_unlocked

inline int in() {
    int n, c;
    while ((c = getchar()) < '0') if (c == EOF) return -1;
    n = c - '0';
    while ((c = getchar()) >= '0') n = n * 10 + c - '0';
    return n;
}

const int MAX_N = 300001;

int i,n,q;
ll ans = 0;
int bt[MAX_N], a[MAX_N], r[MAX_N];
P p[2*MAX_N];

void add(int i, int x){
    while(i < n+1) bt[i] += x, i += i & -i;
}

int sum(int i){
    int s = 0;
    while(i > 0) s += bt[i], i -= i & -i;
    return s;
}

int main()
{
    n = in();
    for(i = 0; i < n; i++){
        a[i] = in();
    }
    for(i = 0; i < n; i++){
        int l = in();
        r[i] = in();
        p[i] = P(a[i], n+i);
        p[n+i] = P(a[i]-l, i);
    }
    sort(p, p+2*n);
    for(i = 0; i < 2*n; i++){
        q = p[i].y;
        if(q >= n){
            q -= n;
            ans += sum(upper_bound(a, a+n, a[q]+r[q]) - a) - sum(q+1);
        }else{
            add(q+1,1);
        }
    }
    printf("%lld\n",ans);
    return 0;
}