#include <bits/stdc++.h>
using namespace std;
#pragma comment(linker, "/STACK:64000000")
int k, res, n, m;
int row[1 << 11];
int main() {
  res = 0;
  scanf("%d%d%d", &n, &m, &k);
  for (int i = 0; i < m; ++i) {
    row[i] = 123456789;
  }
  for (int i = 0; i < n; ++i) {
    int r, c;
    scanf("%d%d", &r, &c);
    --r;
    row[r] = min(row[r], c);
  }
  for (int i = 0; i < m; ++i) {
    if (row[i] >= k) {
      res += k;
      k = 0;
      break;
    }
    k -= row[i];
    res += row[i];
  }
  printf("%d\n", res);
  return 0;
}
