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#include <bits/stdc++.h>

using namespace std;

constexpr uint mod = 1e9 + 7;

uint64_t getms() { return chrono::duration_cast<chrono::milliseconds>(chrono::high_resolution_clock::now().time_since_epoch()).count(); }

vector<size_t> segments(size_t w, size_t l, size_t r)
{
    vector<size_t> nodes;
    for(l += w, r += w; l < r; l /= 2, r /= 2)
    {
        if(l % 2) nodes.emplace_back(l++);
        if(r % 2) nodes.emplace_back(--r);
    }
    return nodes;
}

struct fenwick_tree
{
    size_t n;
    vector<size_t> F;

    fenwick_tree(size_t m) : n(m), F(n+1) {}

    static constexpr size_t lsb(size_t x) { return x & -x; }

    uint get_prefix(size_t p) const
    {
        uint r = 0;
        while(p)
            r = (r + F[p]) % mod, p -= lsb(p);
        return r;
    }

    void delta(size_t p, uint v)
    {
        p++;
        while(p <= n)
            F[p] = (F[p] + v) % mod, p += lsb(p);
    }
};


vector<vector<size_t>> construct_explosion_graph(
    const vector<int64_t>& A, const vector<int64_t>& R)
{
    const size_t n = A.size();

    const size_t w = 1 << __lg(2*n - 1);

    vector<vector<size_t>> graph(2*w);
    for(size_t i = 0; i < n; i++)
    {
        size_t l = lower_bound(A.begin(), A.end(), A[i] - R[i]) - A.begin(),
               r = upper_bound(A.begin(), A.end(), A[i] + R[i]) - A.begin();
        for(auto v : segments(w, l, r))
            graph[i + w].push_back(v);
    }
    for(size_t i = 1; i < w; i++)
        graph[i].push_back(2*i), graph[i].push_back(2*i+1);

    return graph;
}


struct kosaraju_mod
{
    using graph_t = vector<vector<size_t>>;

    const graph_t& graph;
    size_t n;
    vector<bool> vis;

    kosaraju_mod(const graph_t& _graph) : graph(_graph), n(graph.size()), vis(n) {}

    void marker_dfs(size_t u, const graph_t& G, vector<size_t>& out)
    {
        vis[u] = true;
        for(size_t v : G[u])
            if(not vis[v])
                marker_dfs(v, G, out);
        out.push_back(u);
    }

    vector<pair<size_t, size_t>>
    operator() (size_t m, size_t w)
    {
        vector<size_t> order; order.reserve(n);
        fill(vis.begin(), vis.end(), false);
        for(size_t u = 0; u < n; u++)
            if(not vis[u])
                marker_dfs(u, graph, order);

        graph_t graph_T(n);
        for(size_t u = 0; u < n; u++)
            for(size_t v : graph[u])
                graph_T[v].push_back(u);

        fill(vis.begin(), vis.end(), false);
        reverse(order.begin(), order.end());

        vector<size_t> scc_idx(n), curr, left, right, start, finish;
        vector<bool> exists;
        curr.reserve(n); exists.reserve(n);
        left.reserve(n); right.reserve(n);
        start.reserve(n); finish.reserve(n);
        size_t s = 0;
        for(auto u : order)
        {
            if(vis[u]) continue;

            start.push_back(curr.size());
            marker_dfs(u, graph_T, curr);
            finish.push_back(curr.size());

            exists.push_back(false);
            left.push_back(n);
            right.push_back(0);
            for(size_t i = start[s]; i < finish[s]; i++)
            {
                scc_idx[curr[i]] = s;
                if(w <= curr[i] and curr[i] < w+m)
                {
                    exists[s] = true;
                     left[s] = min( left[s], curr[i] - w);
                    right[s] = max(right[s], curr[i] - w);
                }
            }
            s++;
        }
        vector<pair<size_t, size_t>> intervals; intervals.reserve(s);
        for(size_t i = s; i --> 0; )
        {
            for(size_t j = start[i]; j < finish[i]; j++)
              for(auto v : graph[curr[j]])
            {
                 left[i] = min( left[i],  left[scc_idx[v]]);
                right[i] = max(right[i], right[scc_idx[v]]);
            }
            if(exists[i])
                intervals.emplace_back(left[i], right[i]);
        }

        return intervals;
    }
};


vector<pair<size_t, size_t>> get_explosion_intervals(size_t n, const vector<vector<size_t>>& graph)
{
    const size_t w = graph.size() / 2;
    return kosaraju_mod{graph}(n, w);
}


uint count_nondominated_subsets(size_t m, vector<pair<size_t, size_t>> I)
{
    const size_t n = I.size();

    sort(I.begin(), I.end(), [&](const auto& lhs, const auto& rhs) {
        return lhs.first < rhs.first or (lhs.first == rhs.first and lhs.second > rhs.second);
    });
    fenwick_tree F(m+1);
    F.delta(0, +1);
    for(size_t i = n; i --> 0; )
    {
        auto v = F.get_prefix(I[i].second+1 + 1);
        F.delta(0, v); F.delta(I[i].second+1, mod-v);
    }

    return F.get_prefix(0 + 1);
}


int main()
{
    ios::sync_with_stdio(false); cin.tie(nullptr);

    size_t n0;
    cin >> n0;
    vector<int64_t> A(n0), R(n0);
    for(size_t i = 0; i < n0; i++)
        cin >> A[i] >> R[i];

    cout << count_nondominated_subsets(n0, get_explosion_intervals(n0, construct_explosion_graph(A, R))) << endl;
}