题目
思路
AVL树插入算法,输出根即可
代码
#include <iostream>
using namespace std;
typedef struct node {
int val;
struct node* left, * right;
}node,*tree;
void rotateLeft(tree& root) {
node* t = root->right;
root->right = t->left;
t->left = root;
root = t;
}
void rotateRight(tree& root) {
node* t = root->left;
root->left = t->right;
t->right = root;
root = t;
}
void rotateLeftRight(tree& root) {
rotateLeft(root->left);
rotateRight(root);
}
void rotateRightLeft(tree& root) {
rotateRight(root->right);
rotateLeft(root);
}
int getHeight(tree& root) {
if (root == nullptr) return 0;
return max(getHeight(root->left), getHeight(root->right)) + 1;
}
void insert(tree& root, int val) {
if (root == nullptr) {
root = new node();
root->val = val;
root->left = root->right = nullptr;
return;
}
else if (val < root->val) {
insert(root->left, val);
if (getHeight(root->left) - getHeight(root->right) == 2)
val < root->left->val ? rotateRight(root) : rotateLeftRight(root);
}
else {
insert(root->right, val);
if (getHeight(root->left) - getHeight(root->right) == -2)
val > root->right->val ? rotateLeft(root) : rotateRightLeft(root);
}
}
int main() {
int n, val;
scanf_s("%d", &n);
tree root = nullptr;
for (int i = 0; i < n; i++) {
scanf_s("%d", &val);
insert(root, val);
}
printf("%d", root->val);
return 0;
}