#include <bits/stdc++.h>
using namespace std;
int N, M, K;
int v[10005];
int main() {
  scanf("%d%d%d", &N, &M, &K);
  for (int i = 1; i <= N; i++) scanf("%d", &v[i]);
  if (N % 2 == 0) {
    printf("0\n");
    exit(0);
  }
  int mn = 1 << 30;
  for (int i = 1; i <= N; i += 2) mn = min(mn, v[i]);
  int moves = (N + 1) / 2;
  int cnt = M / moves;
  long long ans = min(1LL * mn, 1LL * cnt * K);
  printf("%I64d\n", ans);
  return 0;
}
