#include <bits/stdc++.h>
using namespace std;
const int maxn = 1010;
int n, m;
int k;
int h[maxn];
int main() {
  cin >> n >> m >> k;
  for (int i = 1; i < m + 1; i++) h[i] = 100000000;
  for (int i = 0; i < n; i++) {
    int x, y;
    cin >> x >> y;
    if (y < h[x]) h[x] = y;
  }
  int sum = 0;
  for (int i = 1; i < m + 1; i++) sum += h[i];
  cout << min(sum, k) << endl;
  return 0;
}
