#include <bits/stdc++.h>
using namespace std;
void solve();
int main() {
  ios_base::sync_with_stdio(false);
  cout << fixed;
  cout << setprecision(10);
  int t = 1;
  while (t--) solve();
  return 0;
}
void solve() {
  long long int n, i, j, k;
  cin >> n;
  string ans;
  char s[2100];
  for (i = 1; i <= n; i++) cin >> s[i];
  s[0] = 'o';
  if (n & 1) {
    ans = s[1];
    for (i = 2; i <= n; i++) {
      if (i & 1)
        ans = ans + s[i];
      else
        ans = s[i] + ans;
    }
  } else {
    ans = s[1];
    for (i = 2; i <= n; i++) {
      if (i & 1)
        ans = s[i] + ans;
      else
        ans = ans + s[i];
    }
  }
  cout << ans;
}
