遇到的问题:
力扣108.将所有序数组转换为二叉搜索树
给你一个整数数组 nums ,其中元素已经按 升序 排列,请你将其转换为一棵 高度平衡 二叉搜索树。
高度平衡 二叉树是一棵满足「每个节点的左右两个子树的高度差的绝对值不超过 1 」的二叉树。
提交后显示解答错误,
我的思路是递归以先序遍历的方式从根节点依次创建其左右节点,最后返回根节点指针。目前不知道错因
我的代码:
/**
* Definition for a binary tree node.
* struct TreeNode {
* int val;
* struct TreeNode *left;
* struct TreeNode *right;
* };
*/
struct TreeNode* lr(int *nums, int l, int r, struct TreeNode* rt)
{
if(l>r)
return NULL;
rt=(struct TreeNode*)malloc(sizeof(struct TreeNode));
rt->left=rt->right=NULL;
int mid=l + (r-l)/2;
rt->val=nums[mid];
lr(nums,l,mid-1,rt->left);
lr(nums,mid+1,r,rt->right);
return rt;
}
struct TreeNode* sortedArrayToBST(int* nums, int numsSize){
struct TreeNode *root;
root=lr(nums,0,numsSize-1,root);
return root;
}
执行结果:
这题涉及到的主要问题就是传参,应当使用二级指针作为实参传递,通过的代码如下:
/**
* Definition for a binary tree node.
* struct TreeNode {
* int val;
* struct TreeNode *left;
* struct TreeNode *right;
* };
*/
struct TreeNode* lr(int *nums, int l, int r, struct TreeNode** rt)
{
if(l>r)
return NULL;
struct TreeNode* rtt=(struct TreeNode*)malloc(sizeof(struct TreeNode));
rtt->left=rtt->right=NULL;
int mid=l + (r-l)/2;
rtt->val=nums[mid];
*rt=rtt;
lr(nums,l,mid-1,&(rtt->left));
lr(nums,mid+1,r,&(rtt->right));
return rtt;
}
struct TreeNode* sortedArrayToBST(int* nums, int numsSize){
struct TreeNode *root;
root=lr(nums,0,numsSize-1,&root);
return root;
}
关于传参问题毕竟清晰易懂的解释可以参考这个https://blog.csdn.net/Kukeoo/article/details/114297192?spm=1001.2014.3001.5506
该回答引用ChatGPT
请参考下面的代码
#include<iostream>
#include<cmath>
#include<vector>
using namespace std;
bool is_prime(int n) {
if (n <= 1) return false;
int m = sqrt(n);
for (int i = 2; i <= m; i++) {
if (n % i == 0) return false;
}
return true;
}
int main() {
int num_primes = 0, min_gap = 0x7fffffff, max_gap = 0, gap;
int prime1, prime2;
vector<int> primes;
for (int i = 100000; num_primes < 10000; i++) {
if (is_prime(i)) {
num_primes++;
primes.push_back(i);
if (num_primes >= 2) {
gap = primes[num_primes - 1] - primes[num_primes - 2];
if (gap < min_gap) {
min_gap = gap;
prime1 = primes[num_primes - 2];
prime2 = primes[num_primes - 1];
}
if (gap > max_gap) {
max_gap = gap;
}
}
}
}
cout << "The minimum gap is " << min_gap << " between " << prime1 << " and " << prime2 << endl;
cout << "The maximum gap is " << max_gap << endl;
return 0;
}