#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const ll inf = 1e18;
inline ll divf(ll a, ll b) {
return a/b - ((a^b)<0 && a%b);
}
struct line {
mutable ll m, c, p;
bool operator<(const line &l) const { return m < l.m; }
bool operator<(ll x) const { return p < x; }
};
struct cht : multiset<line, less<>> {
private:
inline ll isect(iterator x, iterator y) {
return divf(x->c-y->c, y->m-x->m);
}
public:
inline void add(ll m, ll c) {
auto y = insert({m, c, inf}), x = y++;
if(empty()) return;
if(x!=begin() && y!=end() && isect(x, y)<=prev(x)->p) {
erase(x);
return;
}
while(y!=end()) {
ll p = isect(x, y);
if(p>=y->p) y = erase(y);
else {
x->p = p;
break;
}
}
if(x==begin()) return;
y = x--;
while(x!=begin() && isect(prev(x), y)<=prev(x)->p) {
erase(x);
x = prev(y);
}
x->p = isect(x, y);
}
inline ll get(ll x) {
assert(!empty());
auto it = lower_bound(x);
return it->m*x + it->c;
}
};
const int MXN = 1e5+5;
int n, h[MXN];
ll w[MXN], dp[MXN];
cht ds;
inline void add(int j) {
ds.add(2*h[j], -(dp[j]+1ll*h[j]*h[j]-w[j]));
}
inline ll get(int i) {
return -ds.get(h[i]) + 1ll*h[i]*h[i] + w[i-1];
}
int32_t main() {
cin.tie(0); cout.tie(0); ios_base::sync_with_stdio(0);
cin >> n;
for(int i=1; i<=n; i++) cin >> h[i];
for(int i=1; i<=n; i++) cin >> w[i], w[i] += w[i-1];
add(1);
for(int i=2; i<=n; i++) {
dp[i] = get(i);
add(i);
}
cout << dp[n] << '\n';
return 0;
}
