#include <bits/stdc++.h>
using namespace std;
vector<int64_t> v[3001];
int64_t calc(int64_t taken, int64_t n, int64_t m) {
  int64_t req = taken - v[0].size();
  int64_t t = v[0].size();
  int64_t ans = 0;
  vector<int64_t> rem;
  for (int64_t i = 1; i < m; i++) {
    if (v[i].size() == 0) continue;
    for (int64_t j = 0; j < v[i].size(); j++) {
      if (j + taken <= v[i].size()) {
        ans += v[i][j];
        req--;
      } else
        rem.push_back(v[i][j]);
    }
  }
  if (req > 0) {
    sort(rem.begin(), rem.end());
    int64_t i = 0;
    while (req > 0 and i < rem.size()) {
      ans += rem[i];
      i++;
      req--;
    }
  }
  return ans;
}
void solve() {
  int64_t n, m, i, ans;
  cin >> n >> m;
  for (int64_t i = 0; i < n; i++) {
    int64_t p, c;
    cin >> p >> c;
    p--;
    v[p].push_back(c);
  }
  for (int64_t i = 0; i < m; i++) {
    sort(v[i].begin(), v[i].end());
  }
  ans = LLONG_MAX;
  for (int64_t i = 1; i <= n; i++) {
    int64_t curr_cost = calc(i, n, m);
    ans = min(ans, curr_cost);
  }
  cout << ans << '\n';
}
signed main() {
  std::ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  solve();
  cerr << " Execution : " << (1.0 * clock()) / CLOCKS_PER_SEC << "s \n";
  return 0;
}
