#include <iostream>
#include <vector>
#include <cstdio>

using namespace std;

typedef long long LL;

const int N = 300010;

int n;
LL a[N], l[N], r[N];
LL ans;

void Solve() {
    scanf("%d", &n);

    for (int i = 1; i <= n; ++i) scanf("%lld", &a[i]);
    for (int i = 1; i <= n; ++i) scanf("%lld%lld", &l[i], &r[i]);

    ans = 0LL;
    for (int i = 1; i <= n; ++i) {
        for (int j = i + 1; j <= n; ++j) {
            if (a[j] <= a[i] + r[i] && a[i] >= a[j] - l[j]) ++ans;
        }
    }

    printf("%lld\n", ans);
}

int main() {
    Solve();

    return 0;
}