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#include <bits/stdc++.h>
using namespace std;
#define REP(i,a,b) for (int i = (a); i <= (b); ++i)
#define REPD(i,a,b) for (int i = (a); i >= (b); --i)
#define FORI(i,n) REP(i,1,n)
#define FOR(i,n) REP(i,0,int(n)-1)
#define mp make_pair
#define pb push_back
#define pii pair<int,int>
#define vi vector<int>
#define ll long long
#define SZ(x) int((x).size())
#define DBG(v) cerr << #v << " = " << (v) << endl;
#define FOREACH(i,t) for (typeof(t.begin()) i=t.begin(); i!=t.end(); i++)
#define fi first
#define se second

const int mod = 1000000007;
const int N = 300300;
const int M = 1 << 19;

int n;
ll a[N], r[N];
int le[N], ri[N], L[M*2+13], R[M*2+13];
int minL[N];
int vis[N];
int DP[N], DPS[N];

int get(int *T, int pos) {
	return T[pos+M];
}

void put(int *T, int pos, int val) {
	pos += M;
	T[pos] = val;
	while (pos > 1) {
		pos /= 2;
		T[pos] = max(T[pos*2], T[pos*2+1]);
	}
}

int argmax(int *T, int posl, int posr) {
	posl += M;
	posr += M+1;
	int res = posl;
	while (posl+1 < posr) {
		if ((posl&1)==0 && T[posl+1]>T[res]) res = posl+1;
		if ((posr&1)==1 && T[posr-1]>T[res]) res = posr-1;
		posl /= 2;
		posr /= 2;
	}
	while (res < M) {
		if (T[res*2] > T[res*2+1]) res = res*2;
		else res = res*2+1;
	}
	return res-M;
}

void gen_rad() {
	FORI(i,n) {
		le[i] = L[i] = lower_bound(a+1, a+n+1, a[i]-r[i]) - a;
		ri[i] = R[i] = lower_bound(a+1, a+n+1, a[i]+r[i]+1) - a-1;
	}
}

void gen_ran() {
	FORI(i,n) R[M+i] = R[i];
	for (int i = M-1; i >= 1; i--) {
		R[i] = max(R[i*2], R[i*2+1]);
	}
	FORI(i,n) if (!vis[i]) {
		vi path;
		int j = i;
		while (!vis[j]) {
			vis[j] = 1;
			path.pb(j);
			j = argmax(R, L[j], get(R,j));
		}
		int ans = get(R,j);
		for (auto x : path) {
			put(R,x,ans);
		}
	}
	FORI(i,n) R[i] = R[M+i];
	FORI(i,n) vis[i]=0;
	FORI(i,n) L[M+i] = n+1-L[i];
	for (int i = M-1; i >= 1; i--) {
		L[i] = max(L[i*2], L[i*2+1]);
	}
	for (int i = n; i >= 1; i--) if (!vis[i]) {
		vi path;
		int j = i;
		while (!vis[j]) {
			vis[j] = 1;
			path.pb(j);
			j = argmax(L, n+1-get(L,j), R[j]);
		}
		int ans = get(L,j);
		for (auto x : path) {
			put(L,x,ans);
		}
	}
	FORI(i,n) L[i] = n+1-L[M+i];
}

void gen_ran_slow() {
	FORI(i,n) {
		//cerr << "i = " << i << "\n";
		int lf = le[i], rf = ri[i];
		int lc = i, rc = i;
		while (lc >= lf || rc <= rf) {
			while (lc >= lf) {
				//cerr << lf << " " << lc << " " << " | " << rc << " " << rf << " -> l " << lc << "(" << le[lc] << " " << ri[lc] << ")\n";
				lf = min(lf, le[lc]);
				rf = max(rf, ri[lc]);
				lc--;
			}
			while (rc <= rf) {
				//cerr << lf << " " << lc << " " << " | " << rc << " " << rf << " -> r " << rc << "(" << le[rc] << " " << ri[rc] << ")\n";
				lf = min(lf, le[rc]);
				rf = max(rf, ri[rc]);
				rc++;
			}
		}
		L[i] = lf;
		R[i] = rf;
	}
}

int main() {
	scanf("%d", &n);
	FORI(i,n) scanf("%lld%lld", &a[i], &r[i]);
	
	gen_rad();
	if (n <= 20000) {
		gen_ran_slow();
	} else {
		gen_ran();
		gen_ran();
		gen_ran();
	}
	
	minL[n] = L[n];
	for (int i = n-1; i >= 1; i--) minL[i] = min(L[i], minL[i+1]);
	
	DP[n+1] = 1;
	DPS[n+1] = 1;
	for (int i = n; i >= 0; i--) {
		DP[i] = DP[i+1];
		for (int j = i+1; j<=n && L[j]>i; j=R[j]+1) {
			if (minL[j]>i) {
				DP[i] += DPS[R[j]+1];
				if (DP[i] >= mod) DP[i] -= mod;
				break;
			}
			DP[i] += DP[R[j]+1];
			if (DP[i] >= mod) DP[i] -= mod;
		}
		DPS[i] = (DP[i] + DPS[R[i]+1]) % mod;
	}
	
	//FORI(i,n) cerr << le[i] << "\t"; cerr << "\n";
	//FORI(i,n) cerr << ri[i] << "\t"; cerr << "\n";
	//FORI(i,n) cerr <<  L[i] << "\t"; cerr << "\n";
	//FORI(i,n) cerr <<  R[i] << "\t"; cerr << "\n";
	//FOR(i,n+1) cerr << DP[i] << "\t"; cerr << "\n";
	//FOR(i,n+1) cerr << DPS[i] << "\t"; cerr << "\n";
	
	printf("%d\n", DP[0]);
	return 0;
}