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#include <bits/stdc++.h>
#define ll long long
#define st first
#define nd second
#define pb push_back
const int N=300005, mod=1e9+7;
using namespace std;
vector<int> V[N], U[N];
int n;
vector<pair<ll, ll> > miny;
ll ans=1;
void bg(int x){
    int y=x-1;
    while(y>=0&&miny[y].st>=miny[x].st-miny[x].nd){
        V[x].pb(y);
        U[y].pb(x);
        --y;
    }
    y=x+1;
    while(y<n&&miny[y].st<=miny[x].st+miny[x].nd){
        V[x].pb(y);
        U[y].pb(x);
        ++y;
    }
}
stack<int> s;
int odw[N], skl[N], nr=0, cur=1;
void dfs(int x){
    odw[x]=1;
    for(int y: V[x]){
        if(!odw[y]) dfs(y);
    }
    s.push(x);
}

void sfd(int x, int nr){
    odw[x]=2;
    skl[x]=nr;
    for(int y: U[x]){
        if(odw[y]<2) sfd(y, nr);
    }
}
vector<int> S[N];
void mrg(int x){
    odw[x]=3;
    for(int y: V[x]){
        if(skl[x]!=skl[y]){
            S[skl[x]].push_back(skl[y]);
        }
        if(odw[y]<3) mrg(y);
    }
}

int vis[N];
vector<int> topsort;
void tsort(int x){
    vis[x]=1;
    for(int y: S[x]){
        if(!vis[y]) tsort(y);
    }
    topsort.push_back(x);
}
int ile[N],dp[N];
void DFS(int x){
    vis[x]=2;
    for(int y: S[x]){
        dp[y]=max(dp[y], dp[y]*(ile[x]+1)%mod);
        cur=max(cur, dp[y]);
        if(vis[y]<2){
            ile[y]=ile[x]+1;
            DFS(y);
        }
    }
}
int main()
{
    ios_base::sync_with_stdio(0);
    cin>>n;
    for(int i=1; i<=n; ++i){
        ll a, r;
        cin>>a>>r;
        miny.pb({a, r});
    }
    sort(miny.begin(), miny.end());
    for(int i=0; i<n; ++i) bg(i);
    for(int i=0; i<n; ++i){
        if(!odw[i]) dfs(i);
    }
    while(!s.empty()){
        int p=s.top();
        s.pop();
        if(odw[p]<2){
            nr++;
            sfd(p, nr);
        }
    }
    for(int i=1; i<=n; ++i){
        if(odw[i]<3) mrg(i);
    }
    for(int i=1; i<=nr; ++i){
        dp[i]=1;
        ile[i]=1;
    }

    for(int i=1; i<=nr; ++i){
        if(!vis[i]){
            tsort(i);
        }
    }
    for(int i=topsort.size()-1; i>=0; --i){
        cur=1;
        if(vis[topsort[i]]<2){
            DFS(topsort[i]);
            if(S[topsort[i]].size()==0) cur=2;
            ans=ans*cur%mod;
        }

    }
    cout<<ans+1;
    return 0;
}