Compressed Number

#include<bits/stdc++.h>

using namespace std;
typedef long long int ll;
//#define isvowel(a) (a == 'a' || a == 'e' || a == 'i' || a == 'o' || a == 'u')
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define gcd __gcd
#define getl(s) getline(cin, s);
#define setpre(x) fixed << setprecision(x)
#define mset(a) memset(a, 0, sizeof(a))
#define endl '\n'
const int N=500050,M=1000000007;
const ll INF=1e18+7;
int n,x[N],y[N],a[N],maxis=1,L,R,sum=0;
int main(){
    ios_base::sync_with_stdio(NULL); cin.tie(nullptr); cout.tie(nullptr);
//    freopen(".inp","r",stdin);
//    freopen(".out","w",stdout);
    set<int>ex;
    vector<int>nein;
    mset(a);
    cin>>n;
    for(int i=0;i<n;++i){
        cin>>x[i]>>y[i];
        ex.insert(x[i]);
        ex.insert(y[i]);
    }
    nein.pb(-M);
    for(auto tmp:ex){
        nein.pb(tmp);
    }
    for(int i=0;i<n;++i){
        ++a[lower_bound(nein.begin(),nein.end(),x[i])-nein.begin()];
        --a[lower_bound(nein.begin(),nein.end(),y[i]+1)-nein.begin()];
    }
    for(int i=1;i<=nein.size();++i){
        a[i]+=a[i-1];
        maxis=max(maxis,a[i]);
    }
    cout<<maxis;
    return 0;
}
/*
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INPUT:                            |
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OUTPUT:                           |
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*/