#include <bits/stdc++.h>
using namespace std;
int N, M, Lim;
int row[1001];
void get_data() { scanf("%d%d%d", &N, &M, &Lim); }
void run() {
  memset(row, -1, sizeof(row));
  int sum = 0, i, r, t;
  for (i = 0; i < N; i++) {
    scanf("%d%d", &r, &t);
    if (row[r] == -1) {
      sum += t;
      row[r] = t;
    } else if (row[r] > t) {
      sum -= row[r] - t;
      row[r] = t;
    }
  }
  if (sum > Lim) sum = Lim;
  printf("%d\n", sum);
}
int main() {
  get_data();
  run();
  return 0;
}
