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#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define pb push_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
typedef vector<int> VI;
typedef long long ll;
typedef pair<int,int> PII;
typedef double db;
//mt19937 mrand(random_device{}()); 
const ll mod=1000000007;
//int rnd(int x) { return mrand() % x;}
ll powmod(ll a,ll b) {ll res=1;a%=mod; assert(b>=0); for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;}
ll gcd(ll a,ll b) { return b?gcd(b,a%b):a;}
// head

const int N=501000;
ll a[N],r[N];
int stk[N],L[N],R[N],n,dp[N];
int c[N];
VI dis[N];
int main() {
	scanf("%d",&n);
	rep(i,1,n+1) scanf("%lld%lld",a+i,r+i);
	a[0]=-(1ll<<60);
	a[n+1]=(1ll<<61);
	r[0]=r[n+1]=(1ll<<62);
	int t=0; stk[t++]=n+1;
	per(i,1,n+1) {
		auto eval=[&](int i) {return a[i]-r[i]; } ;
		int l=0,r=t;
		while (l+1<r) {
			int md=(l+r)>>1;
			if (eval(stk[md])<=a[i]) l=md;
			else r=md;
		}
		R[i]=stk[l];
		while (t>0&&eval(i)<=eval(stk[t-1])) --t;
		stk[t++]=i;
	}
	t=0; stk[t++]=0;
	rep(i,1,n+1) {
		auto eval=[&](int i) {return a[i]+r[i];} ;
		int l=0,r=t;
		while (l+1<r) {
			int md=(l+r)>>1;
			if (eval(stk[md])>=a[i]) l=md;
			else r=md;
		}
		L[i]=stk[l];
		while (t>0&&eval(i)>=eval(stk[t-1])) --t;
		stk[t++]=i;
	}
	R[0]=n+1; L[n+1]=0;
	dp[0]=1;
	rep(i,0,n+1) {
		dis[R[i]].pb(i);
	}
	auto modify=[&](int x,int s) {
		for (;x<=n+2;x+=x&-x) c[x]=(c[x]+s)%mod;
	};
	auto query=[&](int x) {
		int s=0;
		for (;x;x-=x&-x) s=(c[x]+s)%mod;
		return s;
	};
	modify(1,dp[0]);
	rep(i,1,n+2) {
		dp[i]=(query(i)-query(L[i]))%mod;
		for (auto x:dis[i]) modify(x+1,-dp[x]);
		modify(i+1,dp[i]);
	}
	if (dp[n+1]<0) dp[n+1]+=mod;
	printf("%d\n",dp[n+1]);
}