#include <bits/stdc++.h>
using namespace std;
long long n, m, k, a[1005], ans, r, c;
int main() {
  cin >> n >> m >> k;
  for (int i = 1; i <= 1000; i++) a[i] = 1000000007;
  for (int i = 1; i <= n; i++) {
    cin >> r >> c;
    a[r] = min(a[r], c);
  }
  for (int i = 1; i <= m; i++) {
    ans += a[i];
  }
  cout << min(ans, k);
}
