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#include <iostream>
#include <vector>
#include <algorithm>
#include <list>
#include <stack>
#include <queue>
#include <unordered_map>

struct Mine {
    long long pos;
    int directLeftStriking = -1, directRightStriking = -1;
    int nearestLeftActivator = -1, nearestRightActivator = -1;
    int globalLeftStriking = -1, globalRightStriking = -1;
    int globallyNearestLeftActivator = -1, globallyNearestRightActivator = -1;
};

#define DIVISOR 1000000007

namespace std {
    template<> struct hash<std::pair<int, int>> {
        std::size_t operator()(std::pair<int, int> const & p) const noexcept {
            return std::hash<int>{}(p.first) ^ std::hash<int>{}(p.second);
        }
    };
}
std::unordered_map<std::pair<int, int>, int> cache{};

long long countPossibilities(const std::vector<Mine> &mines, int startPos, int endPos) {
    if (startPos > endPos) return 1;
    auto cachedPossibilities = cache.find(std::make_pair(startPos, endPos));
    if (cachedPossibilities != cache.end()) return cachedPossibilities->second;

    long long result = countPossibilities(mines, mines[startPos].globalRightStriking + 1, endPos);
    long long notActivatedResult = 1;
    int startPosIter = startPos;
    while (mines[startPosIter].globallyNearestRightActivator != -1) {
        notActivatedResult *= countPossibilities(mines, startPosIter + 1, mines[startPosIter].globallyNearestRightActivator - 1);
        notActivatedResult %= DIVISOR;
        startPosIter = mines[startPosIter].globallyNearestRightActivator;
    }
    notActivatedResult *= countPossibilities(mines, startPosIter + 1, endPos);
    notActivatedResult %= DIVISOR;
    result += notActivatedResult;
    result %= DIVISOR;
    cache[std::make_pair(startPos, endPos)] = result;
    return result;
}

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

    int n;
    std::cin >> n;
    std::vector<Mine> mines;
    {
        mines.resize(n);
        std::vector<long long> positions, strikes;
        positions.resize(n);
        strikes.resize(n);
        for (int i = 0; i < n; ++i) {
            std::cin >> positions[i] >> strikes[i];
        }
        for (int i = 0; i < n; ++i) {
            mines[i].directLeftStriking = std::distance(positions.begin(), std::lower_bound(positions.begin(), positions.end(), positions[i] - strikes[i]));
            mines[i].directRightStriking = std::distance(positions.begin(), std::upper_bound(positions.begin(), positions.end(), positions[i] + strikes[i])) - 1;
        }
    }
    {
        std::stack<int> rightActivatorsHelper;
        for (int i = 0; i < n; ++i) {
            while (not rightActivatorsHelper.empty()) {
                int top = rightActivatorsHelper.top();
                if (top >= mines[i].directLeftStriking) {
                    rightActivatorsHelper.pop();
                    mines[top].nearestRightActivator = i;
                } else break;
            }
            rightActivatorsHelper.push(i);
        }
    }
    {
        std::stack<int> leftActivatorsHelper;
        for (int i = n - 1; i > -1; --i) {
            while (not leftActivatorsHelper.empty()) {
                int top = leftActivatorsHelper.top();
                if (top <= mines[i].directRightStriking) {
                    leftActivatorsHelper.pop();
                    mines[top].nearestLeftActivator = i;
                } else break;
            }
            leftActivatorsHelper.push(i);
        }
    }
    {
        std::vector<int> rightStrikingOrdered;
        rightStrikingOrdered.reserve(n);
        for (int i = 0; i < n; ++i) {
            rightStrikingOrdered.push_back(i);
        }
        std::sort(rightStrikingOrdered.begin(), rightStrikingOrdered.end(), [&mines](int i1, int i2) { return mines[i1].directRightStriking < mines[i2].directRightStriking; });
        for (int i = n - 1; i > -1; --i) {
            if (mines[i].globalRightStriking != -1) {
                continue;
            }
            mines[i].globalRightStriking = i;
            std::queue<int> bfsHelper;
            bfsHelper.push(i);
            while (not bfsHelper.empty()) {
                int top = bfsHelper.front();
                bfsHelper.pop();
                auto rightActivator = mines[top].nearestRightActivator;
                if (rightActivator != -1 and mines[rightActivator].globalRightStriking == -1) {
                    mines[rightActivator].globalRightStriking = i;
                    bfsHelper.push(rightActivator);
                }
                auto leftActivator = mines[top].nearestLeftActivator;
                if (leftActivator != -1 and mines[leftActivator].globalRightStriking == -1) {
                    mines[leftActivator].globalRightStriking = i;
                    bfsHelper.push(leftActivator);
                }
            }
        }
    }
    {
        std::vector<int> leftStrikingOrdered;
        leftStrikingOrdered.reserve(n);
        for (int i = 0; i < n; ++i) {
            leftStrikingOrdered.push_back(i);
        }
        std::sort(leftStrikingOrdered.begin(), leftStrikingOrdered.end(), [&mines](int i1, int i2) { return mines[i1].directLeftStriking < mines[i2].directLeftStriking; });
        for (int i = 0; i < n; ++i) {
            if (mines[i].globalLeftStriking != -1) {
                continue;
            }
            mines[i].globalLeftStriking = i;
            std::queue<int> bfsHelper;
            bfsHelper.push(i);
            while (not bfsHelper.empty()) {
                int top = bfsHelper.front();
                bfsHelper.pop();
                auto rightActivator = mines[top].nearestRightActivator;
                if (rightActivator != -1 and mines[rightActivator].globalLeftStriking == -1) {
                    mines[rightActivator].globalLeftStriking = i;
                    bfsHelper.push(rightActivator);
                }
                auto leftActivator = mines[top].nearestLeftActivator;
                if (leftActivator != -1 and mines[leftActivator].globalLeftStriking == -1) {
                    mines[leftActivator].globalLeftStriking = i;
                    bfsHelper.push(leftActivator);
                }
            }
        }
    }
    {
        std::stack<int> rightActivatorsHelper;
        for (int i = 0; i < n; ++i) {
            while (not rightActivatorsHelper.empty()) {
                int top = rightActivatorsHelper.top();
                if (top >= mines[i].globalLeftStriking) {
                    rightActivatorsHelper.pop();
                    mines[top].globallyNearestRightActivator = i;
                } else break;
            }
            rightActivatorsHelper.push(i);
        }
    }
    {
        std::stack<int> leftActivatorsHelper;
        for (int i = n - 1; i > -1; --i) {
            while (not leftActivatorsHelper.empty()) {
                int top = leftActivatorsHelper.top();
                if (top <= mines[i].globalRightStriking) {
                    leftActivatorsHelper.pop();
                    mines[top].globallyNearestLeftActivator = i;
                } else break;
            }
            leftActivatorsHelper.push(i);
        }
    }

    std::vector<std::pair<int, int>> separatedGroups;
    int groupStart = 0, maxRelated = 0;
    for (int i = 0; i < n; ++i) {
        if (mines[i].globalRightStriking > maxRelated) maxRelated = mines[i].globalRightStriking;
        if (mines[i].globallyNearestRightActivator > maxRelated) maxRelated = mines[i].globallyNearestRightActivator;
        if (maxRelated == i) {
            separatedGroups.emplace_back(groupStart, i);
            groupStart = i + 1;
        }
    }
    long long result = 1;
    for (auto group : separatedGroups) {
        result *= countPossibilities(mines, group.first, group.second);
        result %= DIVISOR;
        cache.clear();
    }
    std::cout << result << std::endl;
    return 0;
}