#include <bits/stdc++.h>
#define pii pair<int, int>
#define mp make_pair
#define F first
#define S second
#define iter(a) a.begin(), a.end()
using namespace std;
typedef long long ll;
const ll MAX = 2147483647;
int argmin(vector<ll>& a, int x, int y){
return a[x] < a[y] ? x : y;
}
struct SparseTable{
vector<vector<int>> st;
void build(vector<ll>& a){
int n = a.size();
st.resize(n, vector<int>(20));
for(int i = 0; i < n; i++) st[i][0] = i;
for(int i = 1; i < 20; i++){
for(int j = 0; j + (1 << i) - 1 < n; j++){
st[j][i] = argmin(a, st[j][i - 1], st[j + (1 << (i - 1))][i - 1]);
}
}
}
int query(vector<ll>& a, int l, int r){
int lg = __lg(r - l + 1);
return argmin(a, st[l][lg], st[r - (1 << lg) + 1][lg]);
}
};
int n;
vector<ll> a, b;
SparseTable sta, stb;
map<pii, ll> tmp;
ll f2(int l, int r){
if(l > r) return 0;
if(tmp.find(mp(l, r)) != tmp.end()) return tmp[mp(l, r)];
int m = stb.query(b, l, r);
tmp[mp(l, r)] = max({b[m] * (r - l + 1), f2(l, m - 1), f2(m + 1, r)});
//cerr << l << " " << r << " " << m << " " << tmp[mp(l, r)] << "\n";
return tmp[mp(l, r)];
}
ll f1(int l, int r){
if(l > r) return 0;
int m = sta.query(a, l, r);
return max({a[m] * f2(l, r), f1(l, m - 1), f1(m + 1, r)});
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(0);
cin >> n;
a.resize(n);
b.resize(n);
for(int i = 0; i < n; i++) cin >> a[i] >> b[i];
sta.build(a);
stb.build(b);
cout << f1(0, n - 1) << "\n";
return 0;
}
