宜信笔试

#include <iostream>
#include <vector>
#include<math.h>
using namespace std;

struct TreeNode {
	int value;
	TreeNode* left;
	TreeNode* right;
};
///寻找数中节点与给定值 差值最小的点
int findClosest(TreeNode* root, int value)
{    // write your code here...
	// suppose root is not NULL
	int temp;
	int mintt = value;
	int res;
	while (root != NULL){
		if (value == root->value){
			res = root->value;
			return res;
		}
		else if ((value<root->value)&&(root->left!=NULL)){
			root = root->left;
			temp = abs(root->value - value);
			if (mintt >= temp){
				mintt = temp;
				res = root->value;
			}
		}
		else if(root->right!=NULL){
			root = root->right;
			temp = abs(root->value - value);
			if (mintt >= temp){
				mintt = temp;
				res = root->value;
			}
		}
		else
		   return res;
	}
	return res;
}

bool BSTInsert(TreeNode*& p, int element)
{
	if (NULL == p) // 空树
	{
		p = new TreeNode;
		p->value = element;
		p->left = p->right = NULL;
		return true;
	}

	if (element == p->value) // BST中不能有相等的值
		return false;

	if (element < p->value) // 递归
		return BSTInsert(p->left, element);

	return BSTInsert(p->right, element); // 递归
}

bool createBST(TreeNode*& T, vector<int> values, int n)
{
	T = NULL;
	int i;
	for (i = 0; i < n; i++) {
		if (!BSTInsert(T, values[i])){
			return false;
		}
	}
	return true;
}

int main()
{	// test and not consider free the used memory
	int n;
	cin >> n;
	vector<int> values(n, 0);
	for (int i = 0; i < n; i++){
		cin >> values[i];
	}
	TreeNode* T;

	// 并非所有的a[]都能构造出BST,所以，最好对createBST的返回值进行判断
	if (createBST(T, values, n)) {
		int m;
		cin >> m;
		for (int i = 0; i < m; i++){
			int tmp;
			cin >> tmp;
			printf("%d\n", findClosest(T, tmp));
			//cout << findClosest(T, tmp) << endl;
		}
	}
	return 0;
}/*10
32 47 91 20 59 0 1 88 74 62
10
0 1 80 81 82 58 59 60 61 20*/