#include <bits/stdc++.h>
#pragma GCC optimize(2)
using namespace std;
inline int read() {
  char ch = getchar();
  int f = 1;
  while (!isdigit(ch)) {
    if (ch == '-') f = -f;
    ch = getchar();
  }
  int x = 0;
  while (isdigit(ch)) x = x * 10 + ch - '0', ch = getchar();
  return x * f;
}
int main() {
  int n = read(), t, maxi = 0;
  while (n--) maxi = max(maxi, t = read());
  printf("%d\n", t ^ maxi);
  return 0;
}

### Prompt

Construct a Cpp code solution to the problem outlined:

DO YOU EXPECT ME TO FIND THIS OUT?

WHAT BASE AND/XOR LANGUAGE INCLUDES string?

DON'T BYTE OF MORE THAN YOU CAN CHEW

YOU CAN ONLY DISTORT THE LARGEST OF MATHEMATICS SO FAR

SAYING "ABRACADABRA" WITHOUT A MAGIC AND WON'T DO YOU ANY GOOD

THE LAST STACK RUPTURES. ALL DIE. OH, THE EMBARRASSMENT!

I HAVE NO ARRAY AND I MUST SCREAM

ELEMENTS MAY NOT BE STORED IN WEST HYPERSPACE

Input

The first line of input data contains a single integer n (1 ≤ n ≤ 10).

The second line of input data contains n space-separated integers ai (1 ≤ ai ≤ 11).

Output

Output a single integer.

Example

Input

4
2 5 3 1


Output

4

### Response

```cpp
#include <bits/stdc++.h>
#pragma GCC optimize(2)
using namespace std;
inline int read() {
  char ch = getchar();
  int f = 1;
  while (!isdigit(ch)) {
    if (ch == '-') f = -f;
    ch = getchar();
  }
  int x = 0;
  while (isdigit(ch)) x = x * 10 + ch - '0', ch = getchar();
  return x * f;
}
int main() {
  int n = read(), t, maxi = 0;
  while (n--) maxi = max(maxi, t = read());
  printf("%d\n", t ^ maxi);
  return 0;
}

```