#include <bits/stdc++.h>
using namespace std;
long long n, a, b, ans;
vector<long long> v[100005];
vector<long long> res;
long long cost(long long num) {
  res.clear();
  long long sum = 0;
  long long need = num - v[0].size();
  for (long long i = 1; i <= 100000; i++) {
    for (long long j = 0; j < v[i].size(); j++) {
      if (v[i].size() - j >= num) {
        need--;
        sum += v[i][j];
      } else
        res.push_back(v[i][j]);
    }
  }
  sort(res.begin(), res.end());
  for (long long i = 1; i <= need; i++) {
    sum += res[i - 1];
  }
  return sum;
}
int main() {
  scanf("%lld", &n);
  for (long long i = 1; i <= n; i++) {
    scanf("%lld%lld", &a, &b);
    v[a].push_back(b);
  }
  for (long long i = 1; i <= 100000; i++) sort(v[i].begin(), v[i].end());
  long long l = v[0].size(), r = n, m1, m2;
  ans = min(cost(l), cost(r));
  while (l + 2 < r) {
    m1 = l + (r - l) / 3;
    m2 = r - (r - l) / 3;
    long long a1 = cost(m1);
    long long a2 = cost(m2);
    if (a1 > a2)
      l = m1, ans = min(ans, a2);
    else
      r = m2, ans = min(ans, a1);
  }
  printf("%lld\n", ans);
  return 0;
}
