#include <bits/stdc++.h>
using namespace std;
int getmin(int a, int b) {
  if (a < b) return a;
  return b;
}
int main() {
  int n, m, k, rs, i, c, row, a[1010];
  int INF1 = 2000000;
  cin >> n >> m >> k;
  for (i = 1; i <= m; i++) a[i] = INF1;
  for (i = 1; i <= n; i++) {
    cin >> row >> c;
    a[row] = getmin(c, a[row]);
  }
  rs = 0;
  for (i = 1; i <= m; i++)
    if (a[i] != INF1) rs += a[i];
  if (rs < k)
    cout << rs;
  else
    cout << k;
  cout << endl;
  return 0;
}
