#include<iostream>

 #include<cstdio>

 #include<cstring>

 #include<string>

 #include<map>

 #include<set>

 #include<cmath>

 #include<algorithm>

 #include<vector>

 #include<sstream>

 #define lowbot(i) (i&(-i))

 using namespace std;

 typedef long long ll;

 const int maxn = 1e5 + ;

 struct node

 {

     ll x, h, id;

 }a[maxn], b[maxn];

 bool cmp1(node a, node b)

 {

     return a.x < b.x;

 }

 bool cmp2(node a, node b)

 {

     return a.h < b.h;

 }

 bool cmp3(node a, node b)

 {

     return a.h > b.h;

 }

 int n;

 void add(int x, int d, int tree[])

 {

     while(x <= n)

         tree[x] += d, x += lowbot(x);

 }

 ll sum(int x, int tree[])

 {

     ll ans = ;

     while(x)

         ans += tree[x], x -=lowbot(x);

     return ans;

 }

 int tree[maxn], tree_num[maxn];

 int main()

 {

     while(scanf("%d", &n) != EOF)

     {

         memset(a, , sizeof(a));

         memset(b, , sizeof(b));

         memset(tree, , sizeof(tree));

         memset(tree_num, , sizeof(tree_num));

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

             scanf("%lld%lld", &a[i].x, &a[i].h), a[i].id = i;

         sort(a + , a +  + n, cmp1);

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

         {

             if(a[i].x == a[i - ].x)b[a[i].id].x = b[a[i - ].id].x;

             else b[a[i].id].x = i;

         }

         sort(a + , a +  + n, cmp2);

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

         {

             if(a[i].h == a[i - ].h)b[a[i].id].h = b[a[i - ].id].h;

             else b[a[i].id].h = i;

         }

         //for(int i = 1; i <= n; i++)

         //    cout<<b[i].x<<" "<<b[i].h<<endl;

         sort(b + , b +  + n, cmp3);

         ll ans = , cnt, num;

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

         {

             cnt = sum(b[i].x, tree);

             num = sum(b[i].x, tree_num);

             ans += (num * b[i].x - cnt) * b[i].h;

             cnt = sum(n, tree) - cnt;

             num = i - num - ;

             ans += (cnt - num * b[i].x) * b[i].h;

             add(b[i].x, b[i].x, tree);

             add(b[i].x, , tree_num);

         }

         cout<<ans<<endl;

     }

     return ;

 }