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#include <bits/stdc++.h>


using namespace std;


const int MOD = 1000 * 1000 * 1000 + 7;


int add(int x, int y) {
    int ans = x + y;
    if (ans >= MOD) {
        ans -= MOD;
    }

    return ans;
}


int mul(int x, int y) {
    return ((long long) x * y) % MOD;
}


struct Testcase {
    int n;
    vector <long long> pos, rad;

    vector <int> jumpNo, jumpYes;
    vector <map<int,pair<int,int>>> cache;

    void read() {
        cin >> n;

        pos.resize(n);
        rad.resize(n);

        for (int i = 0; i < n; i++) {
            cin >> pos[i] >> rad[i];
        }
    }

    int dpAll(int l, int r) {
        auto res = dp(l, r);
        return add(res.first, res.second);
    }

    pair <int,int> dp(int l, int r) {
        if (l == r) {
            return {1, 1};
        }

        auto it = cache[r].find(l);

        if (it != cache[r].end()) {
            return it->second;
        }

        int ansNo, ansYes;

        if (jumpNo[r] >= l) {
            int pref = dp(l, jumpNo[r]).first;

            if (jumpNo[r] < r - 1) {
                int suff = dpAll(jumpNo[r] + 1, r - 1);
                ansNo = mul(pref, suff);
            } else {
                ansNo = pref;
            }
        } else {
            ansNo = dpAll(l, r - 1);
        }

        if (jumpYes[r] >= l) {
            ansYes = dpAll(l, jumpYes[r]);
        } else {
            ansYes = 1;
        }

        pair <int,int> ans = {ansNo, ansYes};

        cache[r][l] = ans;
        return ans;
    }

    int solve() {
        jumpNo.resize(n, -1);
        jumpYes.resize(n, -1);

        vector <pair<long long, int>> optLeft, optRight, optRightmost;

        for (int i = 0; i < n; i++) {
            long long leftmost = pos[i] - rad[i];

            while (!optLeft.empty() && pos[optLeft.back().second] >= leftmost) {
                leftmost = min(leftmost, optLeft.back().first);
                optLeft.pop_back();
            }

            optLeft.push_back({leftmost, i});
            jumpYes[i] = lower_bound(pos.begin(), pos.end(), leftmost) - pos.begin() - 1;

            long long rightmost = pos[i] + rad[i];

            while (!optRight.empty() && pos[optRight.back().second] >= leftmost) {
                rightmost = max(rightmost, optRight.back().first);
                optRight.pop_back();
            }

            optRight.push_back({rightmost, i});

            if (i > 0) {
                pair <long long, int> e = {pos[i], -1};

                auto it = upper_bound(optRightmost.begin(), optRightmost.end(), e, greater <pair<long long,int>> ());
                if (it != optRightmost.begin()) {
                    jumpNo[i] = prev(it)->second;
                }
            }

            while (!optRightmost.empty() && optRightmost.back().first <= rightmost) {
                optRightmost.pop_back();
            }

            optRightmost.push_back({rightmost, i});
        }

        cache.resize(n);

        return dpAll(0, n - 1);
    }
};


int main() {
    ios_base::sync_with_stdio(false);

    Testcase test;

    test.read();
    cout << test.solve() << '\n';

    return 0;
}