#include <bits/stdc++.h>
using namespace std;
int n, m, k;
int a[1000];
int main() {
  cin >> n >> m >> k;
  for (int i = 0; i < m; i++) a[i] = -1;
  for (int i = 0; i < n; i++) {
    int x, y;
    cin >> x >> y;
    x--;
    if (a[x] == -1 || a[x] > y) a[x] = y;
  }
  int s = 0;
  for (int i = 0; i < m; i++) s += a[i];
  if (s < k)
    cout << s;
  else
    cout << k;
  return 0;
}
