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#pragma GCC optimize("Ofast")
#pragma GCC optimization ("O3")
#pragma GCC optimization ("unroll-loops")
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
using namespace std;
#define mp make_pair
#define eb emplace_back
#define pb push_back
#define e1 first
#define e2 second
#define uint unsigned int
#define ll long long
#define ull unsigned long long
#define ld long double
#define float long double
#define size(x) (int)x.size()
#define satori int testCases; cin>>testCases; while(testCases--)
#define fastio ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0)
#define all(r) begin(r),end(r)
#define time chrono::high_resolution_clock().now().time_since_epoch().count()
typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;
mt19937 rng(chrono::high_resolution_clock().now().time_since_epoch().count());
///////////////////
#define debug if(1)
///////////////////

const int MAXN=3e5+10,base=(1<<19),mod=1e9+7;

int t[base*2],l[MAXN],r[MAXN],dp[MAXN];
ll a[MAXN],b[MAXN];
vector<pair<int,int>> mx,mn;

void update(int u,int v){
	u+=base;
	while(u){
		t[u]+=v;
		if(t[u]>=mod)
			t[u]-=mod;
		if(t[u]<0)
			t[u]+=mod;
		u/=2;
	}
}

int get(int l,int r){
	l+=base;
	r+=base;
	int res=t[l];
	if(l!=r){
		res+=t[r];
		if(res>=mod)
			res-=mod;
	}
	while(l/2!=r/2){
		if(l%2==0){
			res+=t[l+1];
			if(res>=mod)
				res-=mod;
		}
		if(r%2==1){
			res+=t[r-1];
			if(res>=mod)
				res-=mod;
		}
		l/=2;
		r/=2;
	}
	return res;
}

void rem(int lo,int hi,int val){
	if(val>=lo&&val<=hi){
		update(val,-dp[val-1]);
	}
}

void add(int lo,int hi,int val){
	if(val>=lo&&val<=hi){
		update(val,dp[val-1]);
	}
}

int32_t main()
{
	fastio;
	int n,lo,hi,mid,ans;
	cin>>n;
	for(int i=1;i<=n;i++)
		cin>>a[i]>>b[i];
	for(int i=1;i<=n;i++){
		lo=1,hi=i;
		l[i]=i;
		while(lo<=hi){
			mid=(lo+hi)/2;
			if(a[mid]>=a[i]-b[i])
				l[i]=mid,hi=mid-1;
			else
				lo=mid+1;
		}
		lo=i,hi=n;
		r[i]=i;
		while(lo<=hi){
			mid=(lo+hi)/2;
			if(a[mid]<=a[i]+b[i])
				r[i]=mid,lo=mid+1;
			else
				hi=mid-1;
		}
	}
	dp[0]=1;
	mn.eb(mp(0,0));
	mx.eb(mp(mod,0));
	for(int i=1;i<=n;i++){
		dp[i]=dp[i-1];
		if(i>1){
			lo=0,hi=size(mx)-1;
			ans=-1;
			while(lo<=hi){
				mid=(lo+hi)/2;
				if(mx[mid].e1<i)
					ans=mid,hi=mid-1;
				else
					lo=mid+1;
			}
			if(ans!=-1){
				dp[i]+=get(mx[ans-1].e2+1,i);
				if(dp[i]>=mod)
					dp[i]-=mod;
			}
		}
		while(mn.back().e1>=l[i]){
			rem(mn[size(mn)-2].e2+1,mn.back().e2,mn.back().e1);
			mn.pop_back();
		}
		while(mx.back().e1<=r[i]){
			mx.pop_back();
		}
		mx.eb(mp(r[i],i));
		add(mn.back().e2+1,i,l[i]);
		mn.eb(mp(l[i],i));
	}
	int res=0;
	int maxl=n+1;
	for(int i=n;i>=0;i--){
		if(maxl==i+1){
			res+=dp[i];
			if(res>=mod)
				res-=mod;	
		}
		maxl=min(maxl,l[i]);
	}
	cout<<res<<'\n';
}