Contest1260/F.cpp

#include<bits/stdc++.h>
using namespace std;
const int MAX=100005;
struct node{
    int s;
    int e;
}a[MAX];

int n;
bool cmp(node x,node y)
{
    return x.e<y.e;
}
int main()
{
    while(cin>>n,n)
    {
        for(int i=0;i<n;i++)
            scanf("%d %d",&a[i].s,&a[i].e);
        sort(a,a+n,cmp);
        int temp=a[0].e,counter=1;
        for(int i=1;i<n;i++)
        {
            if(a[i].s>=temp)
            {
                counter++;
                temp=a[i].e;
            }
        }
       printf("%d\n",counter);
    }
}