ysh牛逼

```cpp
#include<bits/stdc++.h>
using namespace std;

const int N=1e5+10;

struct yshnb{
    int begin;
    int end;
}dsjnb[N];

bool cmp(yshnb &a,yshnb&b)
{
    return a.end < b.end;
}

int main()
{
    int n;
    cin>>n;

    int index=0;
    while(n--)
    {
        int l,r;
        cin>>l>>r;
        dsjnb[index++]={l,r};
    }
    sort(dsjnb,dsjnb+index,cmp);

    int last_end=dsjnb[0].end;
    int cnt=1;
    for(int i=1;i<index;i++)
    {
        int p=dsjnb[i].begin;
        int q=dsjnb[i].end;

        if(last_end<=p)
        {
            cnt++;
            last_end=q;
        }
    }

    cout<<cnt<<"\n";

    return 0;
}