#include <iostream>
#include <algorithm>
using namespace std;

class ANode {
public:
	int v, height;   //v表示权值,height表示树的高度
	ANode *lchild, *rchild;    //左右孩子的结点信息
};

//建立一个新的结点
ANode* createNode(int v) {
	ANode* node = new ANode;
	node->v = v;
	node->height = 1;
	node->lchild = nullptr;
	node->rchild = nullptr;
	return node;       //返回当前结点
}

//获取结点的高度
int getHegiht(ANode* root) {
	if (root == nullptr) {
		return 0;
	}
	else {
		return root->height;
	}
}

//计算平衡引子
int calBanlanceEle(ANode* root) {
	return getHegiht(root->lchild) - getHegiht(root->rchild);
}

//更新结点root的height
void updateHeight(ANode* root) {
	root->height = max(getHegiht(root->lchild), getHegiht(root->rchild)) + 1;
}

//相关操作:
/*查找操作*/
ANode* search(ANode* root, int value) {
	if (root == nullptr) {
		return nullptr;
	}
	if (value == root->v) {
		return root;
	}
	else if (value > root->v) {
		return search(root->rchild, value);
	}
	else {
		return search(root->lchild, value);
	}
}

/*左旋操作*/
void Aleft_rotate(ANode* &root) {
	ANode* temp = root->rchild;
	root->rchild = temp->lchild;
	temp->lchild = root;

	updateHeight(root);
	updateHeight(temp);
	root = temp;  //temp称为root
}

/*右旋操作*/
void Aright_rotate(ANode* &root) {
	ANode* temp = root->lchild;
	root->lchild = temp->rchild;
	temp->rchild = root;

	updateHeight(root);
	updateHeight(temp);
	root = temp;
}


void Ainsert(ANode* &root, int value) {
	if (root == nullptr) {
		root = createNode(value);
		return;
	}

	if (value == root->v) {
		return;
	}
	else if (value > root->v) {
		Ainsert(root->rchild, value);   //右树调整
		updateHeight(root);
		if (calBanlanceEle(root) == -2) {
			if (calBanlanceEle(root->rchild) == 1) {  //RL型
				Aright_rotate(root->rchild);
				Aleft_rotate(root);
			}
			else if (calBanlanceEle(root->rchild) == -1) { //RR型
				Aleft_rotate(root);
			}
		}
	}
	else {
		Ainsert(root->lchild, value);     //左树调整
		updateHeight(root);
		if (calBanlanceEle(root) == 2) {
			if (calBanlanceEle(root->lchild) == 1) {
				Aright_rotate(root);
			}
			else if (calBanlanceEle(root->lchild) == -1) {
				Aleft_rotate(root->lchild);
				Aright_rotate(root);
			}
		}
	}
}

ANode* buildTree(int data[], int n) {
	ANode* root = nullptr;
	for (int i = 0; i < n; ++i) {
		Ainsert(root, data[i]);
	}
	return root;
}

int main() {

	int a[1001];
	int n;
	cin >> n;
	for (int i = 0; i < n; ++i) {
		cin >> a[i];
	}
	
	ANode* res = buildTree(a, n);
	cout << res->v << endl;

	system("PAUSE");
	return 0;
}