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#include <bits/stdc++.h>
#define ll long long int
#define pb push_back
#define st first
#define nd second
#define pii pair<int,int>
#define mp make_pair
#define pll pair<long long,long long>

using namespace std;

const int nax = 5005;

ll a[nax];
ll r[nax];
int n;

int LOW[nax][22];
int HIGH[nax][22];

int dp[nax][2];

pii inter[nax];

vector<int> endzik[nax];

const int bits = 1445;

bitset<bits> dkd[bits];
bitset<bits> prefix[bits];

const int mod = 1e9 + 7;

void solve()
{

    for(int i=0;i<bits;i++) prefix[0].flip(i);
    for(int i=1;i<bits;i++)
    {
        prefix[i] = prefix[i - 1];
        prefix[i].flip(i);
    }
    cin>>n;
    for(int i=1;i<=n;i++) cin>>a[i]>>r[i];
    for(int i=1;i<=n;i++)
    {
        ll to_low = a[i] - r[i];

        ll to_high = a[i] + r[i];

        int wsk = i;
        while(wsk > 1 && a[wsk - 1] >= to_low) wsk--;
        LOW[i][0] = wsk;

        wsk = i;
        while(wsk < n && a[wsk + 1] <= to_high) wsk++;
        HIGH[i][0] = wsk;
    }

    for(int j=1;j<=13;j++)
    {
        for(int i=1;i<=n;i++)
        {
            int lo = LOW[i][j - 1];
            int hi = HIGH[i][j - 1];

            int mini = 1e9;
            int maxi = -1e9;

            for(int c=lo;c<=hi;c++)
            {
                int cmini = LOW[c][j - 1];
                int cmaxi = HIGH[c][j - 1];
                mini = min(mini,cmini);
                maxi = max(maxi,cmaxi);
            }

            LOW[i][j] = mini;
            HIGH[i][j] = maxi;
        }
    }
    vector<pii> intervals;
    for(int i=1;i<=n;i++)
    {
        inter[i] = mp(LOW[i][13],HIGH[i][13]);
    }

    for(int i=1;i<=n;i++)
    {
        pii cur = inter[i];
        endzik[cur.st].pb(cur.nd);
    }
    for(int i=1;i<=n;i++) sort(endzik[i].begin(),endzik[i].end());

    for(int i=n;i>=1;i--)
    {

        int to = i - 2;

        for(int x : endzik[i]) to = max(to ,x);
        int mini = 1e9;
        for(int x : endzik[i])
        {
            dkd[i].set(x);
        }
        int wsk = 0;
        for(int j=i;j<=to + 1;j++)
        {
            int last = 1e9;
            while(wsk < endzik[i].size() && endzik[i][wsk] < j - 1) wsk++;
            last = endzik[i][wsk];

            dkd[i] |= (dkd[j] & prefix[last - 1]);

        }
    }
    dp[n + 1][0] = 1;

    for(int i=n;i>=1;i--)
    {
        dp[i][0] = dp[i + 1][0] + dp[i + 1][1];
        dp[i][0] %= mod;
        for(int x=0;x<bits;x++)
        {
            if(dkd[i][x] == 0) continue;
            dp[i][1] += dp[x + 1][0];
            dp[i][1] %= mod;
        }
    }

    cout<<((dp[1][0] + dp[1][1]) % mod)<<" ";
}

int main()
{
    solve();

    return 0;
}