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#include<bits/stdc++.h>

using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

#define ST first
#define ND second
#define PB push_back
#define SIZE(a) ((int)a.size())

template<class T, class U>
ostream& operator<<(ostream &stream, pair<T, U> &p) {
    stream << "(" << p.ST << "," << p.ND << ")";
    return stream;
}

template<class T>
ostream& operator<<(ostream &stream, vector<T> &v) {
    stream << "[";
    for(auto elem : v) {
        stream << elem << ", ";
    }
    stream << "]";
    return stream;
}

const int mod = 1e9+7;

int main() {
    ios_base::sync_with_stdio(0);
    int n;
    cin >> n;
    vector<ll> a(n), r(n);
    map<ll, int> m;
    for(int i=0; i < n; i++) {
        cin >> a[i] >> r[i];
        m[a[i]-r[i]] = 0;
        m[a[i]] = 0;
        m[a[i]+r[i]] = 0;
    }
    int num = 0;
    for(auto &x : m) {
        x.ND = num++;
    }
    vector<pii> v(n);
    vector<int> p(n);
    for(int i=0; i < n; i++) {
        v[i] = {m[a[i]-r[i]], m[a[i]+r[i]]};
        p[i] = m[a[i]];
    }
    bool flag = true;
    while(flag) {
        flag = false;
        stack<pii> s;
        for(int i=0; i < n; i++) {
            while(!s.empty() && v[i].ST <= s.top().ND) {
                int j = s.top().ST;
                if(v[j].ST < v[i].ST || v[i].ND < v[j].ND) {
                    v[i] = {min(v[i].ST, v[j].ST), max(v[i].ND, v[j].ND)};
                    flag = true;
                }
                s.pop();
            }
            s.push({i, p[i]});
        }
        while(!s.empty()) {
            s.pop();
        }
        for(int i=n-1; i >= 0; i--) {
            while(!s.empty() && s.top().ND <= v[i].ND) {
                int j = s.top().ST;
                if(v[j].ST < v[i].ST || v[i].ND < v[j].ND) {
                    v[i] = {min(v[i].ST, v[j].ST), max(v[i].ND, v[j].ND)};
                    flag = true;
                }
                s.pop();
            }
            s.push({i, p[i]});
        }
    }
    vector<pii> seg(n);
    for(int i=0; i < n; i++) {
        int le=0, ri = i;
        while(le < ri) {
            int mid = (le+ri)/2;
            if(p[mid] < v[i].ST) {
                le=mid+1;
            } else {
                ri=mid;
            }
        }
        seg[i].ST = le;
        le=i, ri=n-1;
        while(le < ri) {
            int mid = (le+ri+1)/2;
            if(v[i].ND < p[mid]) {
                ri=mid-1;
            } else {
                le=mid;
            }
        }
        seg[i].ND = ri;
    }
    // cout << seg << "\n";
    vector<vector<ll>> dp(n+1, vector<ll>(2, 0));
    vector<pii> g(n, {-1, -1}); //parent, end
    dp[0][0] = 1;
    int ptr = 0;
    sort(seg.begin(), seg.end(), [](pii &a, pii &b){return pii(a.ND,a.ST) < pii(b.ND,b.ST);});
    for(int i=0; i < n; i++) {
        dp[i+1][0] = (dp[i][1]+dp[i][0])%mod;
        dp[i+1][1] = 0;
        pii s = {-1, -1};
        while(ptr < n && seg[ptr].ND == i) {
            s = seg[ptr];
            for(int j=s.ST+1; j <= s.ND+1 && j < n; j++) {
                if(g[j].ST < s.ST) {
                    g[j].ST = s.ST;
                }
            }
            if(g[s.ST].ST == -1) {
                for(int j=s.ST-1; j >= 0; j--) {
                    if(g[j].ND >= s.ST-1) {
                        g[s.ST].ST = j;
                        g[s.ST].ND = s.ND; 
                        break;
                    }
                }
            }
            ptr++;
        }
        while(s.ST != -1) {
            dp[i+1][1]+=dp[s.ST][0];   
            s = g[s.ST];
        }
        dp[i+1][1] = (dp[i+1][1])%mod;
        // cout << i << " " << dp[i+1] << "\n";
    }
    cout << ((dp[n][0]+dp[n][1])%mod+mod)%mod << "\n";
}