#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m, k;
  cin >> n >> m >> k;
  map<int, int> mm;
  for (int i = 0; i < n; i++) {
    int r, c;
    cin >> r >> c;
    if (mm.count(r))
      mm[r] = min(mm[r], c);
    else
      mm[r] = c;
  }
  int ans = 0;
  for (map<int, int>::iterator p = mm.begin(); p != mm.end(); p++)
    ans += p->second;
  cout << min(k, ans) << endl;
  return 0;
}
