This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define two pair<int,int>
#define pb push_front
#define f first
#define s second
#define sz(container) (int)(container.size())
inline int bin(int &x){
	x=0;
	char ch=getchar_unlocked();
	while (ch<'0'||ch>'9') ch=getchar_unlocked();
	while (ch>='0'&&ch<='9') x=(x<<3)+(x<<1)+ch-'0',ch=getchar_unlocked();
	return x;
}
int n,x,y;
deque<two>st;
int main(){
bin(n);
while(n--){
	bin(x);
	y=bin(y);
	bool ok=1;
	while(!st.empty()){
		int a=st.front().f;
		int b=st.front().s;
		if(x-a<=b-y){
			ok=0;
			break;
		}
		if(x-a<=y-b){
			st.pop_front();
		}else{
			break;
		}
	}
	if(ok){
		st.pb({x,y});
	}
}
printf("%d\n",sz(st));
	// you should actually read the stuff at the bottom
}
/* stuff you should look for
	* int overflow, array bounds
	* special cases (n=1?), slow multiset operations
	* do smth instead of nothing and stay organized
	* unordered_map, hash_map, scanf, calculate answer instead of ans*K
*/
/*
                   *         *
                  * *       * *
                 *   *     *   *
                *     *   *     *
                 *   *   * *   *
                  *   *   *   *
                   *   * *   *
                     *  *   *
					   *  *
*/
| # | Verdict | Execution time | Memory | Grader output | 
|---|
| Fetching results... | 
| # | Verdict | Execution time | Memory | Grader output | 
|---|
| Fetching results... | 
| # | Verdict | Execution time | Memory | Grader output | 
|---|
| Fetching results... | 
| # | Verdict | Execution time | Memory | Grader output | 
|---|
| Fetching results... | 
| # | Verdict | Execution time | Memory | Grader output | 
|---|
| Fetching results... | 
| # | Verdict | Execution time | Memory | Grader output | 
|---|
| Fetching results... | 
| # | Verdict | Execution time | Memory | Grader output | 
|---|
| Fetching results... |