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#include <iostream>
#include <vector>
#include <algorithm>
#include <map>
#include <cassert>
using namespace std;
const int N = 300005, MOD = 1e9+7, C = 1<<19;
int n;
long long a[N], r[N];
int direct_beg[N], direct_end[N];

void rescale() {
    for (int i=0; i<n; i++) {
        direct_beg[i] = lower_bound(a, a+n, a[i]-r[i]) - a;
        direct_end[i] = upper_bound(a, a+n, a[i]+r[i]) - a - 1;
    }
}

pair<int, int> mintree[2*C], maxtree[2*C];
int min_direct_beg(int a, int b) {
    a += C; b += C;
    auto res = min(mintree[a], mintree[b]);
    while (a/2 != b/2) {
        if (a%2 == 0) res = min(res, mintree[a+1]);
        if (b%2) res = min(res, mintree[b-1]);
        a /= 2; b /= 2;
    }
    return res.second;
}
int max_direct_end(int a, int b) {
    a += C; b += C;
    auto res = max(maxtree[a], maxtree[b]);
    while (a/2 != b/2) {
        if (a%2 == 0) res = max(res, maxtree[a+1]);
        if (b%2) res = max(res, maxtree[b-1]);
        a /= 2; b /= 2;
    }
    return res.second;
}

vector<int> v[N];
void build_graph() {
    for (int i=0; i<n; i++) mintree[C+i] = {direct_beg[i], i};
    for (int i=0; i<n; i++) maxtree[C+i] = {direct_end[i], i};
    for (int i=C-1; i>0; i--) mintree[i] = min(mintree[2*i], mintree[2*i+1]);
    for (int i=C-1; i>0; i--) maxtree[i] = max(maxtree[2*i], maxtree[2*i+1]);
    for (int i=0; i<n; i++) {
        int beg = direct_beg[i], end = direct_end[i];
        int left = min_direct_beg(beg, end);
        int right = max_direct_end(beg, end);
        if (left != i) v[i].push_back(left);
        if (right != i && right != left) v[i].push_back(right);
    }
}

int indirect_beg[N], indirect_end[N];
vector<int> vertices, scc, vr[N];
int vis[N];
bool finished[N];
void dfs_rev(int a) {
    vis[a] = 1;
    for (int b: vr[a]) if (vis[b] != 1) dfs_rev(b);
    vertices.push_back(a);
}
void dfs(int a) {
    vis[a] = 2;
    scc.push_back(a);
    for (int b: v[a]) if (vis[b] != 2) dfs(b);
}
void calc_scc_ranges() {
    for (int i=0; i<n; i++)
        for (int j: v[i])
            vr[j].push_back(i);
    for (int i=0; i<n; i++) if (vis[i] != 1) dfs_rev(i);
    reverse(vertices.begin(), vertices.end());
    for (int x: vertices) {
        if (vis[x] == 2) continue;
        dfs(x);
        int beg = direct_beg[x], end = direct_end[x];
        for (int y: scc) {
            beg = min(beg, direct_beg[y]);
            end = max(end, direct_end[y]);
            for (int z: v[y]) {
                if (!finished[z]) continue;
                beg = min(beg, indirect_beg[z]);
                end = max(end, indirect_end[z]);
            }
        }
        for (int y: scc) {
            indirect_beg[y] = beg;
            indirect_end[y] = end;
            finished[y] = true;
        }
        scc.clear();
    }
}

int ftree[N];
void add(int x, int val) {
    x += 2;
    while (x < N) {
        ftree[x] = (ftree[x] + val) % MOD;
        x += x&(-x);
    }
}
int prefsum(int x) {
    x += 2;
    long long res = 0;
    while (x) {
        res += ftree[x];
        x -= x&(-x);
    }
    return res % MOD;
}

int ind[N];
int dp() {
    for (int i=0; i<n; i++) ind[i] = i;
    sort(ind, ind+n, [&](int a, int b) { return indirect_beg[a] < indirect_beg[b] || (indirect_beg[a] == indirect_beg[b] && indirect_end[a] > indirect_end[b]); });
    add(-1, 1);
    for (int i=0; i<n; i++) {
        int x = ind[i];
        if (i > 0 && indirect_beg[x] == indirect_beg[ind[i-1]] && indirect_end[x] == indirect_end[ind[i-1]]) continue;
        add(indirect_end[x], prefsum(indirect_end[x]-1));
    }

    return prefsum(n);
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cin >> n;
    for (int i=0; i<n; i++) cin >> a[i] >> r[i];
    
    rescale();
    build_graph();
    calc_scc_ranges();
    cout << dp() << "\n";
    return 0;
}