#include<bits/stdc++.h>
using namespace std;

struct query{
    int x;
    int type; // 0: insert, 1: count
    int y;
    int idx;
    query(int _x, int _type, int _y, int _idx): x(_x), type(_type), y(_y), idx(_idx){}
    bool operator<(const query & rhs){
        if (x < rhs.x){
            return true;
        }else if (x > rhs.x){
            return false;
        }else if (type < rhs.type){
            return true;
        }else if (type > rhs.type){
            return false;
        }else{
            return y < rhs.y;
        }
    }
};

int compress_y(vector<query> & que){
    vector<pair<int, int>> ys(que.size());
    for (int i = 0; i < que.size(); ++i) {
        ys[i].first = que[i].y;
        ys[i].second = i;
    }
    sort(ys.begin(), ys.end());
    int pos = 0;
    que[ys[0].second].y = pos;
    for (int i = 1; i < que.size(); ++i){
        if (ys[i].first > ys[i - 1].first) ++pos;
        que[ys[i].second].y = pos;
    }
    return pos;
}

struct BIT{
    vector<int> bit;
    BIT(int n) : bit(n, 0){}
    int sum(int j){
        int s = 0;
        for (; j >= 0; j = (j & (j + 1)) - 1) s += bit[j];
        return s;
    }
    void add(int k, int a) {for (; k < bit.size(); k |= k + 1) bit[k] += a;}
};


int main(){
    cin.tie(0);
    ios::sync_with_stdio(false);
    int N;
    cin >> N;
    vector<int> As(N, 0);
    for (auto & a : As) cin >> a;
    vector<int> Ls(N, 0);
    vector<int> Rs(N, 0);
    for (int i = 0; i < N; ++i){
        cin >> Ls[i] >> Rs[i];
    }
    vector<query> que;
    for (int i = 0; i < N; ++i){
        que.emplace_back(As[i], 0, As[i] - Ls[i], i);
        que.emplace_back(As[i] + Rs[i], 1, As[i], i);
    }
    sort(que.begin(), que.end());
    int max_y = compress_y(que);
    BIT bit(max_y + 1);

    vector<pair<int, int>> aidx(N);
    for (int i = 0; i < N; ++i){
        aidx[i].first = As[i];
        aidx[i].second = i;
    }
    sort(aidx.begin(), aidx.end());
    vector<int> cum(N, 0);
    for (int i = 0; i < N; ++i){
        cum[aidx[i].second] = i + 1;
    }

    long long ans = 0;
    for (auto & q : que){
        if (q.type == 0){
            bit.add(q.y, 1);
        }else{
            ans += bit.sum(q.y) - cum[q.idx];
        }
    }
    cout << ans << endl;
    return 0;
}