题目1463：招聘会

#include <iostream>
#include <stdio.h>
#include <vector>
#include <string>
#include <set>
#include <stack>
#include <queue>
#include <math.h>
#include <time.h>
#include <map>
#include <algorithm>
#include<memory.h>
#include <limits.h>
#define MAX 0x0fffffff
using namespace std;
 
class TL
{
public:
    int st;
    int en;
    TL(int st,int en)
    {
        this->st = st;
        this->en = en;
    }
    TL()
    {
        st = en =-1;
    }
};
bool cmp(TL tl1,TL tl2)
{
    if(tl1.en<tl2.en)return true;
    return false;
}
TL V[1001];
int k = 0;
void Init()
{
    k = 0;
}
int main()
{
    //freopen("D:\\input.txt","r",stdin);
    int n;
    while(cin>>n)
    {
        Init();
        int st,en;
        for(int i=0;i<n;i++)
        {
            cin>>st>>en;
            V[i] = TL(st,en);
            k++;
        }
        sort(V,V+k,cmp);
        int total = 0;
        int pre = 0;
        for(int i=0;i<k;i++)
        {
            if(V[i].st>=pre)
            {
                total++;
                pre = V[i].en;
            }
        }
        cout<<total<<endl;
    }
}
 
 
 
 
 
 
 
 
/**************************************************************
    Problem: 1463
    User: cust123
    Language: C++
    Result: Accepted
    Time:10 ms
    Memory:1528 kb
****************************************************************/