#include<bits/stdc++.h>
using namespace std;
const int N=100005;
mt19937 rnd(time(0));
struct dt
{
    int l,r,len,v;
    bool operator<(const dt &a)const
    {
        return (len==a.len?l<a.l:len<a.len);
    }
}a[N];
int f[N*2];
int n;
inline void ins(int x,int y)
{
    for (;x<=n*2;x+=x&(-x))
        f[x]^=y;
}
inline int ask(int x)
{
    int ans=0;
    for (;x;x-=x&(-x))
        ans^=f[x];
    return ans;
}
int g[N],h[N];
void raodong()
{
    for (int i=1;i<=n/20;++i)
    {
        g[i]=rnd()%n+1;
        h[i]=rnd()%n+1;
        while (g[i]==h[i])
        {
            h[i]=rnd()%n+1;
        }
        swap(a[g[i]],a[h[i]]);
    }
}
void roll_back()
{
    for (int i=n/20;i;--i)
    {
        swap(a[g[i]],a[h[i]]);
    }
}
int main()
{
    scanf("%d",&n);
    for (int i=1;i<=n;++i)
    {
        scanf("%d%d",&a[i].l,&a[i].r);
        a[i].len=a[i].r-a[i].l;
        a[i].len=min(a[i].len,n*2-a[i].len);
        a[i].v=rnd();
        // a[i+n]={a[i].r,a[i].l,n*2-a[i].len};
    }
    sort(a+1,a+1+n);
    int ans=0;
    for (int t=1;t<=100;++t)
    {
        int sum=0;
        for (int i=1;i<=n;++i)
            if (ask(a[i].l-1)==ask(a[i].r))
            {
                ++sum;
                ins(a[i].l,a[i].v);
                ins(a[i].r,a[i].v);
            }
        if (sum>ans)
        {
            ans=sum;
        }
        else
        {
            if (sum<ans)
                roll_back();
        }
        if (n==1)
            break;
        raodong();
        for (int i=1;i<=2*n;++i)
            f[i]=0;
    }
    printf("%d\n",ans);
    return 0;
}