11
3    5
1    4
12  14
8   12
0    6
8   11
6   10
5    7
3    8
5    9
2   13

4

HYNU

#include<iostream>
#include<algorithm>
using namespace std;
struct stu
{
	int a;
	int b;
}s[1005];
bool cmp(stu x,stu y)
{
	return x.b<y.b;
}
int main()
{   
	//freopen("1.txt","r",stdin);
	int n,i;
	while(scanf("%d",&n)!=EOF)
	{
	for(i=0;i<n;i++)
	{
		scanf("%d %d",&s[i].a,&s[i].b);
	}
	sort(s,s+n,cmp);
	int cnt=1;
	int min=s[0].b;
	for(i=1;i<n;i++)
	{
		if(min<=s[i].a)
		{
			min=s[i].b;
		    cnt++;
		}
	}
	printf("%d\n",cnt);
	}
	return 0;
}