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fix(tree): add c codes

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This commit is contained in:
reanon 2023-01-16 10:35:59 +08:00
parent 00009c8e49
commit b1c69a9cdb
2 changed files with 41 additions and 20 deletions
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2
codes/c/chapter_tree/avl_tree.c
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@ -201,8 +201,8 @@ TreeNode *search(avlTree *tree, int val) {
TreeNode *cur = tree->root; TreeNode *cur = tree->root;
// 循环查找，越过叶结点后跳出 // 循环查找，越过叶结点后跳出
while (cur != NULL) { while (cur != NULL) {
// 目标结点在 root 的右子树中
if (cur->val < val) { if (cur->val < val) {
// 目标结点在 root 的右子树中
cur = cur->right; cur = cur->right;
} else if (cur->val > val) { } else if (cur->val > val) {
// 目标结点在 root 的左子树中 // 目标结点在 root 的左子树中

59
codes/c/chapter_tree/binary_search_tree.c
View File

@ -54,11 +54,15 @@ TreeNode *search(binarySearchTree *bst, int num) {
// 循环查找，越过叶结点后跳出 // 循环查找，越过叶结点后跳出
while (cur != NULL) { while (cur != NULL) {
// 目标结点在 root 的右子树中 // 目标结点在 root 的右子树中
if (cur->val < num) cur = cur->right; if (cur->val < num) {
cur = cur->right;
} else if (cur->val > num) {
// 目标结点在 root 的左子树中 // 目标结点在 root 的左子树中
else if (cur->val > num) cur = cur->left; cur = cur->left;
} else {
// 找到目标结点，跳出循环 // 找到目标结点，跳出循环
else break; break;
}
} }
// 返回目标结点 // 返回目标结点
return cur; return cur;
@ -72,17 +76,25 @@ TreeNode *insert(binarySearchTree *bst, int num) {
// 循环查找，越过叶结点后跳出 // 循环查找，越过叶结点后跳出
while (cur != NULL) { while (cur != NULL) {
// 找到重复结点，直接返回 // 找到重复结点，直接返回
if (cur->val == num) return NULL; if (cur->val == num) {
return NULL;
}
pre = cur; pre = cur;
// 插入位置在 root 的右子树中 if (cur->val < num) {
if (cur->val < num) cur = cur->right; // 插入位置在 root 的右子树中
cur = cur->right;
} else {
// 插入位置在 root 的左子树中 // 插入位置在 root 的左子树中
else cur = cur->left; cur = cur->left;
}
} }
// 插入结点 val // 插入结点 val
TreeNode *node = newTreeNode(num); TreeNode *node = newTreeNode(num);
if (pre->val < num) pre->right = node; if (pre->val < num) {
else pre->left = node; pre->right = node;
} else {
pre->left = node;
}
return node; return node;
} }
@ -97,6 +109,7 @@ TreeNode *getInOrderNext(TreeNode *root) {
} }
/* 删除结点 */ /* 删除结点 */
// 由于引入了 stdio.h ，此处无法使用 remove 关键词
TreeNode *removeNode(binarySearchTree *bst, int num) { TreeNode *removeNode(binarySearchTree *bst, int num) {
// 若树为空，直接提前返回 // 若树为空，直接提前返回
if (bst->root == NULL) return NULL; if (bst->root == NULL) return NULL;
@ -106,23 +119,31 @@ TreeNode *removeNode(binarySearchTree *bst, int num) {
// 找到待删除结点，跳出循环 // 找到待删除结点，跳出循环
if (cur->val == num) break; if (cur->val == num) break;
pre = cur; pre = cur;
// 待删除结点在 root 的右子树中 if (cur->val < num) {
if (cur->val < num) cur = cur->right; // 待删除结点在 root 的右子树中
cur = cur->right;
} else {
// 待删除结点在 root 的左子树中 // 待删除结点在 root 的左子树中
else cur = cur->left; cur = cur->left;
}
} }
// 若无待删除结点，则直接返回 // 若无待删除结点，则直接返回
if (cur == NULL) return NULL; if (cur == NULL) {
// 子结点数量 = 0 or 1 return NULL;
}
// 判断待删除结点是否存在子结点
if (cur->left == NULL || cur->right == NULL) { if (cur->left == NULL || cur->right == NULL) {
/* 子结点数量 = 0 or 1 */
// 当子结点数量 = 0 / 1 时， child = nullptr / 该子结点 // 当子结点数量 = 0 / 1 时， child = nullptr / 该子结点
TreeNode *child = cur->left != NULL ? cur->left : cur->right; TreeNode *child = cur->left != NULL ? cur->left : cur->right;
// 删除结点 cur // 删除结点 cur
if (pre->left == cur) pre->left = child; if (pre->left == cur) {
else pre->right = child; pre->left = child;
} } else {
// 子结点数量 = 2 pre->right = child;
else { }
} else {
/* 子结点数量 = 2 */
// 获取中序遍历中 cur 的下一个结点 // 获取中序遍历中 cur 的下一个结点
TreeNode *nex = getInOrderNext(cur->right); TreeNode *nex = getInOrderNext(cur->right);
int tmp = nex->val; int tmp = nex->val;