#include<bits/stdc++.h>

 #define inf 0x3f3f3f3f

 const int maxn=;

 using namespace std;

 typedef long long ll;

 int n;

 ll cnt;

 ll ans;

 ll tot;

 vector<ll> seg;

 map<ll,int> m;

 struct node{

  ll l,r;

 }s[maxn+];

 ll a[maxn+];

 ll c[maxn+];

 ll t[maxn+];

 int lowbit(int x){

    return x&(-x);

 }

 void add(int x,int y){

     while(x<=cnt){

         c[x]+=y;

         x+=lowbit(x);

     }

 }

 ll sum(int x){

     ll res=;

     while(x){

         res+=c[x];

         x-=lowbit(x);

     }

     return res;

 }

 int main()

 {

     scanf("%d",&n);

     for(int i=;i<=n;i++){

         scanf("%I64d%I64d",&s[i].l,&s[i].r);

         seg.push_back(s[i].l);

         seg.push_back(s[i].r);

     }

     unique(seg.begin(),seg.end());

     sort(seg.begin(),seg.end());

     for(size_t i=;i<seg.size();i++){

            if(i==){

                   a[++cnt]=;

                   t[cnt]=cnt;

                   m[seg[i]]=cnt;

            } else {

            if(seg[i]-seg[i-]==){

                 a[++cnt]=;

                 m[seg[i]]=cnt;

                 t[cnt]=cnt;

            } else {

               a[++cnt]=seg[i]-seg[i-]-;

               t[cnt]=cnt;

               a[++cnt]=;

               m[seg[i]]=cnt;

               t[cnt]=cnt;

            }

            }

     }

     for(int i=;i<=n;i++){

         int x=m[s[i].l];

         int y=m[s[i].r];

         swap(t[x],t[y]);

     }

     for(int i=;i<=cnt;i++){

         tot+=a[i];

         add(t[i],a[i]);

         int temp=sum(t[i])-;

         ans+=(tot-temp-)*a[i];

     }

     printf("%I64d\n",ans);

     return ;

 }