#include <bits/stdc++.h>
const long long int maxn = 2e7 + 5;
const long long mod = 1e9 + 7;
using namespace std;
long long int power(long long int a, long long int b) {
  long long int res = 1;
  while (b > 0) {
    if (b % 2 == 1) res = res * a;
    a = a * a;
    b = b / 2;
  }
  return res;
}
long long po(long long x, long long y) {
  long long res = 1;
  x = x % mod;
  while (y > 0) {
    if (y & 1) res = ((res % mod) * (x % mod)) % mod;
    y = y >> 1;
    x = ((x % mod) * (x % mod)) % mod;
  }
  return res;
}
int dp[3001][3001];
int n;
vector<pair<long long int, long long int> > p(3001);
int fun(int i, int pp) {
  if (i >= n) return 0;
  if (dp[i][pp] != -1) return dp[i][pp];
  return dp[i][pp] = min(p[i].second + fun(i + 1, i),
                         abs(p[i].first - p[pp].first) + fun(i + 1, pp));
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  int t = 1;
  while (t--) {
    memset(dp, -1, sizeof(dp));
    cin >> n;
    for (int i = 0; i < n; i++) cin >> p[i].first >> p[i].second;
    p.resize(n);
    sort((p).begin(), (p).end());
    cout << p[0].second + fun(1, 0) << '\n';
  }
}
