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#include <bits/stdc++.h>
#define ll long long
const int MX = 301005;
const int MXNODES = MX * 3 * 4;
const int M = 1000000007;	
using namespace std;
map<ll, int> sk;
ll pozz[MX], lborder[MX], rborder[MX], reach;
int n, N, pref[MX * 4], num[MX * 4];

int idx[MXNODES];

int nodes;
vector<int> g[MXNODES][2];	
int scc[MXNODES];
bitset<MXNODES> visit;
stack<int> stos;
int K;
int maxl[MXNODES], maxr[MXNODES];

int dp[MX], maxlewy, maxprawy;

void add_edge(int a, int b) {
	if(a == b) return;
	g[a][0].push_back(b);
	g[b][1].push_back(a);
}
void build(int pos, int l, int r) {
	if(pref[r] - pref[l - 1]) {
		if(l == r) {
			idx[pos] = num[l];
		} else idx[pos] = ++nodes;
		if(pos > 1) {
			add_edge(idx[pos >> 1], idx[pos]);
		}
	} else return;

	if(l == r) return;
	int m = (r + l) >> 1;
	build(pos << 1, l, m);
	build(pos << 1 | 1, m + 1, r);
}

void detonuj(int pos, int l, int r, int ql, int qr, int from) {
	if(l > qr || r < ql) return;
	if(!idx[pos]) return;
	if(l >= ql && r <= qr) {
		add_edge(from, idx[pos]);
		return;
	}
	int m = (r + l) >> 1;
	detonuj(pos << 1, l, m, ql, qr, from);
	detonuj(pos << 1 | 1, m + 1, r, ql, qr, from);
}

void dfs(int v) {
	visit[v] = 1;
	for(auto u : g[v][0])
		if(!visit[u])
			dfs(u);
	stos.push(v);
}

void dfs2(int v) {
	scc[v] = K;
	for(auto u : g[v][1]) {
		if(!scc[u] && visit[u])
			dfs2(u);
	}
}

void policz(int v) {
	visit[v] = 1;
	for(auto u : g[v][0]) {
		if(!visit[u] && scc[u] != scc[v])
			policz(u);
		maxl[scc[v]] = min(maxl[scc[v]], maxl[scc[u]]);
		maxr[scc[v]] = max(maxr[scc[v]], maxr[scc[u]]);
	}
}
int32_t main() {
	ios_base::sync_with_stdio(0);
	cin >> n;
	for(int i = 1; i <= n; i++) {
		cin >> pozz[i] >> reach;
		lborder[i] = pozz[i] - reach;
		rborder[i] = pozz[i] + reach;
		sk[pozz[i]]++;
		sk[lborder[i]]++;
		//sk[lborder[i] - 1]++;
		sk[rborder[i]]++;
		//sk[rborder[i] + 1]++;
	}

	for(auto &i: sk) {
		i.second = ++N;
	}

	for(int i = 1; i <= n; i++) {
		pozz[i] = sk[pozz[i]];
		pref[pozz[i]]++;
		lborder[i] = sk[lborder[i]];
		rborder[i] = sk[rborder[i]];
		num[pozz[i]] = i;
	}

	for(int i = 1; i <= N; i++) {
		pref[i] += pref[i - 1];
	}

	nodes = n;
	build(1, 1, N);

	for(int i = 1; i <= n; i++) {
		detonuj(1, 1, N, lborder[i], rborder[i], i);
	}

	for(int i = 1; i <= nodes; i++) {
		maxl[i] = 923493203;
		if(!visit[i])
			dfs(i);
	}

	while(!stos.empty()) {
		int w = stos.top();
		stos.pop();
		if(!scc[w])
			K++, dfs2(w);
		if(w <= n) {
			maxl[scc[w]] = min(maxl[scc[w]], w);
			maxr[scc[w]] = max(maxr[scc[w]], w);
		}
	}

	visit.reset();
	for(int i = 1; i <= nodes; i++) {
		if(!visit[i])
			policz(i);
	}
	maxlewy = 1; maxprawy = 1;
	for(int i = 1; i <= n; i++) {
		maxlewy = min(maxlewy, maxl[scc[i]]);
		maxprawy = max(maxprawy, maxr[scc[i]]);
		if(maxlewy == 1 && maxprawy == i)
			dp[i]++;
	}

	dp[0] = 1;
	dp[1]++;
	for(int i = 2; i <= n; i++) {
		dp[i] += dp[i - 1];
		if(dp[i] >= M) dp[i] -= M;
		maxlewy = i; maxprawy = i;
		for(int j = i; j <= n; j++) {
			maxlewy = min(maxlewy, maxl[scc[j]]);
			maxprawy = max(maxprawy, maxr[scc[j]]);
			if(maxlewy == i && maxprawy == j) {
				dp[j] += dp[i - 2];
				if(dp[j] >= M) dp[j] -= M;
			}
		}
	}

	cout << dp[n] << "\n";
}