#include <iostream>
#include <vector>
#include <algorithm>
#include <queue>

using namespace std;

typedef long long LL;
typedef pair<int, int> PII;

const int N = 300010;

int n, lidx[N], ridx[N];
LL a[N], ans;
priority_queue<PII, vector<PII>, greater<PII>> pq;

struct BIT {
    int tr[N];
    void Add(int idx, int val) {
        for (; idx <= n; idx += idx & -idx) tr[idx] += val;
    }
    int Sum(int idx) {
        int res = 0;
        for (; idx > 0; idx -= idx & -idx) res += tr[idx];
        return res;
    }
    int Query(int l, int r) {
        if (l > r) return 0;
        return Sum(r) - Sum(l - 1);
    }
};
BIT bit;

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

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

    for (int i = 1; i <= n; ++i) {
        LL l, r;
        scanf("%lld%lld", &l, &r);
        LL left = a[i] - l, right = a[i] + r;
        lidx[i] = lower_bound(a + 1, a + n + 1, left) - a;
        ridx[i] = upper_bound(a + 1, a + n + 1, right) - a - 1;
    }

    ans = 0LL;
    for (int i = 1; i <= n; ++i) {
        while (!pq.empty() && pq.top().first < i) {
            int idx = pq.top().second;
            pq.pop();
            bit.Add(idx, -1);
        }

        int l = lidx[i];
        if (l <= i - 1) ans += bit.Query(l, i - 1);

        bit.Add(i, 1);
        pq.push(PII(ridx[i], i));
    }

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

int main() {
    Solve();

    return 0;
}