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#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <queue>
#include <stack>
#include <cstdio>
#include <set>
#include <map>
#include <string>
#include <queue>
#include <stack>
#include <unordered_map>
#include <bitset>
using namespace std;

typedef long long int LL;
typedef long double LD;
typedef vector<int> VI;
typedef vector<LL> VLL;
typedef vector<LD> VLD;
typedef vector<string> VS;
typedef pair<int, int> PII;
typedef vector<PII> VPII;

const int INF = 1000000001;
const LD EPS = 10e-9;

#define FOR(x, b, e) for(int x = b; x <= (e); ++x)
#define FORD(x, b, e) for(int x = b; x >= (e); --x)
#define REP(x, n) for(int x = 0; x < (n); ++x)
#define VAR(v, n) __typeof(n) v = (n)
#define ALL(c) (c).begin(), (c).end()
#define SIZE(x) ((int)(x).size())
#define FORE(i, c) for(VAR(i, (c).begin()); i != (c).end(); ++i)
#define MP make_pair
#define PB push_back
#define ST first
#define ND second
#define abs(a) ((a)<0 ? -(a) : (a))
#define max(a, b) ((a) > (b) ? (a) : (b))
#define min(a, b) ((a) < (b) ? (a) : (b))

const int MAX_N = 300005;
const LL P = 1000000007;

struct Mine
{
    LL pos, rad;
};

int n;
LL a, r;
Mine mines[MAX_N];
bool nothingDetonates = true;
unordered_map<int, vector<int>> detonates;
set<int> results;

LL pow2(int x)
{
    LL base = 2;
    LL res = 1;

    while(x > 0)
    {
        if(x%2 == 1)
        {
            res = (res * base) % P;
        }
        base = (base * base) % P;

        x /= 2;
    }

    return res;
}

void prepareDetonates()
{
    for(int i = 0; i < n; ++i)
    {
        vector<int> toDetonate;

        for(int j = i-1; j >= 0; --j)
        {
            const LL dist = abs(mines[i].pos - mines[j].pos);
            if(dist > mines[i].rad)
            {
                break;
            }

            nothingDetonates = false;
            toDetonate.push_back(j);
        }

        for(int j = i+1; j < n; ++j)
        {
            const LL dist = abs(mines[i].pos - mines[j].pos);
            if(dist > mines[i].rad)
            {
                break;
            }

            nothingDetonates = false;
            toDetonate.push_back(j);
        }

        detonates[i] = toDetonate;
    }
}

void simulate(const int startingMines)
{
    queue<int> toDetonate;
    bitset<32> detonated;

    for(int i = 0; i < n; ++i)
    {
        if((startingMines & (1<<i)) != 0)
        {
            toDetonate.push(i);
            detonated[i] = true;
        }
    }

    while(!toDetonate.empty())
    {
        const int mineIdx = toDetonate.front();
        toDetonate.pop();

        for(const int mineToAdd : detonates[mineIdx])
        {
            if(!detonated[mineToAdd])
            {
                toDetonate.push(mineToAdd);
                detonated[mineToAdd] = true;
            }
        }
    }

    results.insert(detonated.to_ulong());
}

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

    prepareDetonates();

    if(nothingDetonates || n > 27)
    {
        cout << pow2(n) << endl;
        return 0;
    }

    const int upperBound = (1 << n);
    for(int i = 0; i < upperBound; ++i)
    {
        simulate(i);
    }

    cout << results.size() << endl;

    return 0;
}