二叉树快速查找

来源：互联网发布：mac装win10好吗编辑：程序博客网时间：2024/04/30 10:07

#include <iostream>
#include <string.h>
using namespace std;

class TreeNode{
public:
   char n[10];
   TreeNode *left;
   TreeNode *right;
   TreeNode(){
       left = NULL;
       right = NULL;
   }
};

bool flag = false;
void search_and_insert(TreeNode *root, TreeNode *current);
int compare(char *a, char *b);
void deleteall(TreeNode *node);
int main()
{
   int k;
   int n;
   cin>>k;
   TreeNode *root;
   for(int i=0 ;i<k; i++)
   {
       cin>>n;
       flag = false;
       for(int j=0; j<n; j++)
       {

           if(j==0)
           {
               root = new TreeNode();
               cin>>root->n;
           }
           else
           {
               TreeNode * current = new TreeNode();
               cin>>current->n;
               if(!flag)
                   search_and_insert(root, current);
               if(flag)
                   delete current;
           }
       }

       if(flag)
           cout<<"NO"<<endl;
       else
           cout<<"YES"<<endl;
       deleteall(root);
   }
   return 0;
}

void search_and_insert(TreeNode *root, TreeNode *current)
{
   TreeNode *temp = root;
   while(temp!=NULL)
   {
       int result = compare(temp->n, current->n);
       if(result == 0)
           return;
       else if(result == 1)
       {
           if(temp->left == NULL)
           {
               temp->left = current;
               return;
           }
           else
               temp = temp->left;
       }

       else if(result == -1)
       {
           if(temp->right == NULL)
           {
               temp->right = current;
               return;
           }
           else
               temp = temp->right;
       }
   }
}

int compare(char *a, char *b)
{
   int lena = strlen(a);
   int lenb = strlen(b);
   int min = lena>lenb ? lenb : lena;
   for(int i=0; i<min; i++)
   {
       if(a[i] > b[i])
           return 1;
       else if(a[i] < b[i])
           return -1;
   }

   flag = true;

   return 0;
}

void deleteall(TreeNode *node)
{
   if(node->left!=NULL)
       deleteall(node->left);
   if(node->right!=NULL)
       deleteall(node->right);
   delete node;
}