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#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<bool> vb;
typedef vector<int> vi;
typedef vector<vector<int>> vvi;
typedef vector<ll> vl;
typedef vector<vector<ll>> vvl;
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define mt make_tuple
#define st first
#define nd second
#define FOR(__VAR, __START, __END) for(int __VAR=__START; __VAR<=__END; __VAR++)
#define FORB(__VAR, __START, __END) for(int __VAR=__START; __VAR>=__END; __VAR--)
#define FORK(__VAR, __START, __END, __DIFF) for(int __VAR=__START; __VAR<=END; __VAR+=__DIFF)
#define all(__VAR) (__VAR).begin(), (__VAR).end()
#define rall(__VAR) (__VAR).rbegin(), (__VAR).rend()
#define DEBUG(__VAR) cout << #__VAR << ": " << __VAR;

template<typename __T1, typename __T2>
ostream & operator<<(ostream &out, pair<__T1, __T2> &__VAR)
{
	cout << "[" << __VAR.st << ", " << __VAR.nd << "]";
	return out;
}

template<typename __T>
ostream & operator<<(ostream &out, vector<__T> &__VAR)
{
	cout << "[";
	FOR(i, 0, (int)__VAR.size()-2)
		cout << __VAR[i] << ", ";
	if(__VAR.size()>0)
		cout << __VAR[__VAR.size()-1];
	cout << "]" << endl;
	
	return out;
}

const ll INF=2e18, MOD=1e9+7LL;

class minmaxTree { //{min,max} na przedziale
private:
	ll treeSize=1LL;
	vector<pll> v;
	
	//0 - min, 1 - max
	ll query(ll left, ll right, ll cur, ll p, ll q, bool type) {
		if(right<p || q<left) {
			if(type)
				return 0LL;
			return INF;
		}
		if(p<=left && right<=q) {
			if(type)
				return v[cur].nd;
			return v[cur].st;
		}
		ll mid=(left+right)/2LL;
		if(type)
			return max(query(left,mid,2LL*cur,p,q,type),query(mid+1LL,right,2LL*cur+1LL,p,q,type));
		return min(query(left,mid,2LL*cur,p,q,type),query(mid+1LL,right,2LL*cur+1LL,p,q,type));
	}
	
public:
	minmaxTree(ll N) {
		while(treeSize<N)
			treeSize*=2LL;
		v.resize(2LL*treeSize, {INF,0LL});
	}
	
	void insert(ll pos, pll val) {
		pos+=treeSize-1LL;
		v[pos]=val;
		while(pos/=2LL) {
			auto [a1,b1]=v[2LL*pos];
			auto [a2,b2]=v[2LL*pos+1LL];
			v[pos]={min(a1,a2),max(b1,b2)};
		}
	}
	
	ll getMin(ll p, ll q) {
		return query(1LL,treeSize,1LL,p,q,false);
	}
	
	ll getMax(ll p, ll q) {
		return query(1LL,treeSize,1LL,p,q,true);
	}
};

class segmentTree {
private:
	ll treeSize=1;
	vector<ll> sum;
	
	ll query(ll left, ll right, ll cur, ll p, ll q) {
		if(right<p || q<left)
			return 0LL;
		if(p<=left && right<=q)
			return sum[cur];
		ll mid=(left+right)/2LL;
		return (query(left,mid,2*cur,p,q)+query(mid+1,right,2*cur+1,p,q))%MOD;
	}
	
public:
	segmentTree(ll N) {
		while(treeSize<N)
			treeSize*=2LL;
		sum.resize(2LL*treeSize,0);
	}
	
	void insert(ll pos, ll val) {
		pos+=treeSize-1LL;
		sum[pos]=val%MOD;
		while(pos/=2LL)
			sum[pos]=(sum[2*pos]+sum[2*pos+1])%MOD;
	}
	
	ll getSum(ll p, ll q) {
		return query(1,treeSize,1,p,q);
	}
	
	void print() {
		cout << "TREE: ";
		for(int i=1; i<2*treeSize; i++) {
			if((i&-i)==i)
				cout << endl;
			cout << sum[i] << ' ';
		}
		cout << endl;
	}
};

int main()
{
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);

	ll n;
	cin >> n;
	vector<ll> a(n+1, -INF), r(n+1, 0LL);
	for(int i=1; i<=n; i++)
		cin >> a[i] >> r[i];
	
	vector<ll> rightRange(n+1, 0LL);
	minmaxTree rangeTree(n);
	for(ll i=n; i>0; i--) {
		auto it=upper_bound(a.begin(), a.end(), a[i]+r[i]);
		it--;
		rightRange[i]=max(a[i]+r[i], rangeTree.getMax(i, it-a.begin()));
		rangeTree.insert(i, {INF,rightRange[i]});
	}
	
	vector<ll> leftRange(n+1, INF);
	for(ll i=1; i<=n; i++) {
		auto it=lower_bound(a.begin()+1, a.end(), a[i]-r[i]);
		leftRange[i]=min(a[i]-r[i], rangeTree.getMin(it-a.begin(), i));
		rangeTree.insert(i, {leftRange[i], 0});
	}
	
	vector<pll> dp(1, {-INF,0});
	for(ll i=1; i<=n; i++)
		dp.pb({rightRange[i],0});
	sort(dp.begin(), dp.end());
	auto last=unique(dp.begin(), dp.end());
	dp.erase(last, dp.end());
	for(ll i=0; i<dp.size(); i++)
		dp[i].nd=(ll)(i+1);
	segmentTree tree(dp.size());
	vector<ll> res(n+1, 0LL);
	res[0]=1LL;
	tree.insert(1, 1);
	
	for(ll i=1; i<=n; i++) {
		auto itDP=lower_bound(dp.begin(), dp.end(), mp(rightRange[i],0LL));
		ll j=itDP->nd; //index dp w drzewie;
		
		auto it=lower_bound(a.begin(), a.end(), leftRange[i]);
		it--;
		ll k=it-a.begin(); //index res
		
		tree.insert(j, (res[k]-tree.getSum(j+1, dp.size())+MOD)%MOD);
		
		itDP=lower_bound(dp.begin(), dp.end(), mp(a[i],0LL));
		itDP--;
		ll l=itDP->nd; //index pref do res;
		res[i]=(res[k]+tree.getSum(1,l))%MOD;
	}
	
	cout << res[n] << '\n';

	return 0;
}