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#include<stdio.h>
#include<cstring>
#include<cstdlib>
#include<cmath>
#include<iostream>
#include<algorithm>
#include<vector>
#include<map>
#include<set>
#include<queue>
#include<bitset>
#include<utility>
#include<functional>
#include<iomanip>
#include<sstream>
#include<ctime>
#include<cassert>
using namespace std;
#define y0 y0z
#define y1 y1z
#define yn ynz
#define j0 j0z
#define j1 j1z
#define jn jnz
#define tm tmz
#define buli(x) (__builtin_popcountll(x))
#define bur0(x) (__builtin_ctzll(x))
#define bul2(x) (63-__builtin_clzll(x))
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define fil(a,b) memset((a),(b),sizeof(a))
#define cl(a) fil(a,0)
#define siz(x) ((int)(x).size())
#define all(x) (x).begin(),(x).end()
#define foreach(it,a) for(__typeof((a).begin()) it=(a).begin();it!=(a).end();it++)
#define rep(i,a,b) for (int i=(a),_ed=(b);i<_ed;i++)
#define per(i,a,b) for (int i=(b)-1,_ed=(a);i>=_ed;i--)
#define forg(i,gu) for (int i=gu;~i;i=e[i].next)
#define pw(x) ((ll(1))<<(x))
#define upmo(a,b) (((a)=((a)+(b))%mo)<0?(a)+=mo:(a))
#define mmo(a,b) (((a)=1ll*(a)*(b)%mo)<0?(a)+=mo:(a))
void getre(){int x=0;printf("%d\n",1/x);}
void gettle(){int res=1;while(1)res<<=1;printf("%d\n",res);}
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<pii> vpii;
template<typename T,typename S>inline bool upmin(T&a,const S&b){return a>b?a=b,1:0;}
template<typename T,typename S>inline bool upmax(T&a,const S&b){return a<b?a=b,1:0;}
template<typename N,typename PN>inline N flo(N a,PN b){return a>=0?a/b:-((-a-1)/b)-1;}
template<typename N,typename PN>inline N cei(N a,PN b){return a>0?(a-1)/b+1:-(-a/b);}
template<typename N>N gcd(N a,N b){return b?gcd(b,a%b):a;}
template<typename N>inline int sgn(N a){return a>0?1:(a<0?-1:0);}
#if ( ( _WIN32 || __WIN32__ ) && __cplusplus < 201103L)
#define lld "%I64d"
#else
#define lld "%lld"
#endif
inline void gn(long long&x){
	int sg=1;char c;while(((c=getchar())<'0'||c>'9')&&c!='-');c=='-'?(sg=-1,x=0):(x=c-'0');
	while((c=getchar())>='0'&&c<='9')x=x*10+c-'0';x*=sg;
}
inline void gn(int&x){long long t;gn(t);x=t;}
inline void gn(unsigned long long&x){long long t;gn(t);x=t;}
inline void gn(double&x){double t;scanf("%lf",&t);x=t;}
inline void gn(long double&x){double t;scanf("%lf",&t);x=t;}
inline void gs(char *s){scanf("%s",s);}
inline void gc(char &c){while((c=getchar())>126 || c<33);}
inline void pc(char c){putchar(c);}
#ifdef JCVB
#define debug(...) fprintf(stderr, __VA_ARGS__)
#else
#define debug(...)
#endif
typedef long long ll;
typedef double db;
inline ll sqr(ll a){return a*a;}
inline db sqrf(db a){return a*a;}
const int inf=0x3f3f3f3f;
//const ll inf=0x3f3f3f3f3f3f3f3fll;
const db pi=3.14159265358979323846264338327950288L;
const db eps=1e-6;
const int mo=1e9+7;
//int qp(int a,ll b){int n=1;do{if(b&1)n=1ll*n*a%mo;a=1ll*a*a%mo;}while(b>>=1);return n;}

const int N = 533333;

int n;

ll cen[N],rad[N];
int baor[N],baol[N];

int dfn[N],low[N];int timestamp=0;
int sccid[N],scccnt=0;int stk[N],top=0;
int minchoice(int i,int j){
	if(dfn[i]<=dfn[j]) return i;
	else return j;
}
int segdfn[N*4];
int l1,r1,segupdx,segupdI;
int segans;
int scclefcov[N],sccrigcov[N];

int segmin[N*4],segmax[N*4];

void updmin(int* seg, int l,int r,int x) {
	if(l==r) {
		seg[x]=segupdx;
	} else {
		int mid=l+r>>1;
		if(segupdI<=mid) updmin(seg,l,mid,x<<1);
		else updmin(seg,mid+1,r,x<<1|1);
		seg[x]=min(seg[x<<1],seg[x<<1|1]);
	}
}
void quemin(int *seg,int l,int r,int x) {
	if(l1<=l && r<=r1) {
		segans = min(segans, seg[x]);
	}else {
		int mid=l+r>>1;
		if(l1<=mid)quemin(seg,l,mid,x<<1);
		if(r1>mid)quemin(seg,mid+1,r,x<<1|1);
	}

}

void upd(int* seg, int l,int r,int x) {
	if(l==r) {
		seg[x]=segupdx;
	} else {
		int mid=l+r>>1;
		if(segupdI<=mid) upd(seg,l,mid,x<<1);
		else upd(seg,mid+1,r,x<<1|1);
		seg[x]=minchoice(seg[x<<1],seg[x<<1|1]);
	}
}
void que(int* seg, int l,int r,int x) {
	if(l1<=l && r<=r1) {
		segans = minchoice(segans, seg[x]);
	}else {
		int mid=l+r>>1;
		if(l1<=mid)que(seg,l,mid,x<<1);
		if(r1>mid)que(seg,mid+1,r,x<<1|1);
	}
}
void tarjan(int u) {
	dfn[u]=low[u]=++timestamp;
	stk[++top]=u;
	segupdI=u;
	segupdx=u;
	upd(segdfn,1,n,1);
	while(1) {
		segans = 0;
		l1=baol[u];r1=baor[u];
		que(segdfn,1,n,1);
		if(dfn[segans]==0) {
			int v = segans;
			tarjan(v);
			low[u]=min(low[u],low[v]);
		} else break;
	}
	segans = 0; l1=baol[u];r1=baor[u];
	que(segdfn,1,n,1);
	low[u] = min(low[u],dfn[segans]);
	if(low[u]==dfn[u]) {
		++scccnt;
		scclefcov[scccnt]=sccrigcov[scccnt]=u;
		int oldtop=top;
		do {
			sccid[stk[top]]=scccnt;
			upmin(scclefcov[scccnt],baol[stk[top]]);
			upmax(sccrigcov[scccnt],baor[stk[top]]);
			segupdI=stk[top];
			segupdx=0;
			upd(segdfn,1,n,1);
			top--;
		}while(stk[top+1]!=u);

		l1 = scclefcov[scccnt],r1=sccrigcov[scccnt];
		segans = inf;
		quemin(segmin,1,n,1);
		scclefcov[scccnt]=segans;
		segans = inf;
		quemin(segmax,1,n,1);
		sccrigcov[scccnt]=-segans;
		rep(j,top+1,oldtop+1) {
			segupdI = stk[j];
			segupdx = scclefcov[scccnt];
			updmin(segmin,1,n,1);
			segupdx = -sccrigcov[scccnt];
			updmin(segmax,1,n,1);
		}
	}
}

vector<int> dian[N];

int bit[N];
void bitupd(int x,int d){
	for (;x<=n;x+=x&-x)upmo(bit[x],d);
}
int bitque(int x) {
	int su=0;
	for(;x;x-=x&-x)upmo(su,bit[x]);
	return su;
}
int main()
{
#ifdef JCVB
	//freopen("1.in","r",stdin);
	//freopen("1.out","w",stdout);
	int _time_jc=clock();
#endif
	dfn[0]=inf;
	gn(n);
	rep(i,1,n+1) {
		segupdI=i;
		segupdx=i;
		upd(segdfn,1,n,1);
		segupdI=i;
		segupdx=i;
		updmin(segmin,1,n,1);
		segupdI=i;
		segupdx=-i;
		updmin(segmax,1,n,1);
	}
	rep(i,1,n+1) {
		gn(cen[i]);
		gn(rad[i]);
	}

	rep(i,1,n+1) {
		baor[i] = upper_bound(cen+1,cen+1+n,cen[i]+rad[i])-cen-1;
		baol[i] = lower_bound(cen+1,cen+1+n,cen[i]-rad[i])-cen;
	}
	rep(i,1,n+1) {
		if(!dfn[i]) tarjan(i);
	}
	rep(i,1,scccnt+1) {
		dian[sccrigcov[i]].pb(scclefcov[i]);
	}

	rep(i,1,n+1) {
		vector<int> res;
		rep(j,0,siz(dian[i])) {
			int r=1;
			upmo(r, bitque(dian[i][j]-1));
			res.pb(r);
		}
		rep(j,0,siz(dian[i])) {
			bitupd(dian[i][j],res[j]);
		}
	}
	printf("%d\n",(bitque(n)+1)%mo);
#ifdef JCVB
	debug("time: %d\n",int(clock()-_time_jc));
#endif
	return 0;
}