#include <bits/stdc++.h>
using namespace std;
int main() {
  int t;
  t = 1;
  while (t--) {
    long long n, i, j, w, h, count = 0, sum = 0, total, k, T, m, r, c;
    string s;
    cin >> n >> m >> k;
    vector<int> v(m + 1);
    for (i = 1; i <= m; i++) {
      v[i] = -1;
    }
    for (i = 0; i < n; i++) {
      cin >> r >> c;
      if (v[r] == -1 || v[r] > c) {
        v[r] = c;
      }
    }
    for (i = 1; i <= m; i++) {
      sum = sum + v[i];
    }
    cout << min(sum, k);
  }
}
