#include <bits/stdc++.h>
using namespace std;
constexpr long double pi{3.1415926535897932384};
constexpr long long mod{1000000007};
long long power(long long x, long long y) {
  long long res = 1;
  x = x % mod;
  while (y > 0) {
    if (y & 1) res = (res * x) % mod;
    y = y >> 1;
    x = (x * x) % mod;
  }
  return res;
}
long long gcd(long long a, long long b) {
  if (a == 0) return b;
  return gcd(b % a, a);
}
long long lcm(long long a, long long b) { return (a / gcd(a, b) * b); }
pair<long long, long long> v[3001];
long long n, dp[3001][3001];
const long long INF = 1000000000000000;
long long getAns(long long pos, long long pre) {
  if (pos > n) return 0;
  if (dp[pos][pre] != -INF) return dp[pos][pre];
  long long x = v[pos].second + getAns(pos + 1, pos);
  long long y = v[pos].first - v[pre].first + getAns(pos + 1, pre);
  return dp[pos][pre] = min(x, y);
}
signed main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  ;
  cin >> n;
  for (long long i = 1; i <= n; i++) {
    cin >> v[i].first >> v[i].second;
  }
  sort(v + 1, v + n + 1);
  for (long long i = 0; i <= n; i++) {
    for (long long j = 0; j <= n; j++) {
      dp[i][j] = -INF;
    }
  }
  long long ans = getAns(2, 1) + v[1].second;
  cout << ans << '\n';
  return 0;
}
