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

#define endl '\n'
#define L long long
#define MP make_pair
#define REP(i, n) for(int i = 0; i < n; ++i)
#define REPR(i, n) for(int i = n - 1; i >= 0; --i)
#define FOR(i, a, b) for(int i = a; i < b; ++i)
#define FORR(i, a, b) for(int i = b - 1; i >= a; --i)
#define EB emplace_back
#define ST first
#define ND second
#define S size()
#define RS resize

using VI = vector<int>;
using VVI = vector<VI>;
using PI = pair<int, int>;
using VPI = vector<PI>;
using VVPI = vector<VPI>;
using VL = vector<L>;
using VVL = vector<VL>;
using VB = vector<bool>;
using VC = vector<char>;

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    
    L mod = 1e9 + 7;
    int n;
    cin >> n;
    VL a(n), r(n);
    REP(i, n)
        cin >> a[i] >> r[i];
        
    VVI prze(n);
    REP(i, n)
    {
        int k = i;
        L lr = a[i] - r[i], rr = a[i] + r[i];
        while (k < n && (i == 0 || a[i - 1] < lr))
        {   
            if (k == n - 1 || a[k + 1] > rr)
                prze[k].EB(i);
            k++;
            if (k != n)
            {
                lr = min(lr, a[k] - r[k]);
                rr = max(rr, a[k] + r[k]);
            }
        }
    }
    
    VL dp(n), pref(n);
    REP(i, n)
    {
        for (int p : prze[i])
        {
            dp[i] += 1L;
            if (p - 2 >= 0)
                dp[i] += pref[p - 2];
        }
        if (dp[i] >= mod)
            dp[i] %= mod;
        dp[i] %= mod;
        pref[i] = dp[i];
        if (i > 0)
            pref[i] += pref[i - 1];
        if (pref[i] >= mod)
            pref[i] %= mod;
    }
    
    L wynik = 1;
    REP(i, n)
        wynik += dp[i];
    wynik %= mod;
    
    cout << wynik;
}