二分探索木で要素を検索するC++プログラム

このプログラムでは、する必要があります。二分探索を実装して、二分探索ツリー内の検索シーケンスの存在を見つけます。二分探索の最悪の場合の時間計算量はO（n）ですが、平均的な場合はO（log（n））です。

アルゴリズム

Begin
   Construct binary search tree for the given unsorted data array by inserting data into tree one by one.
   Take the input of data to be searched in the BST.
   Now starting from the root node, compare the data with data part of the node.
   if data < temp->d, move the temp pointer to the left child.
   if data > temp->d move the temp pointer to the right child.
   if data = temp->d print the tree depth where it is found and return to main.
   Else print item not found.
End

サンプルコード

#include<iostream>
using namespace std;
struct node {
   int d;
   node *left;
   node *right;
};
node* CreateNode(int d) {
   node *newnode = new node;
   newnode->d = d;
   newnode->left = NULL;
   newnode->right = NULL;
   return newnode;
}
node* InsertIntoTree(node* root, int d) {
   node *temp = CreateNode(d);
   node *t = new node;
   t = root;
   if(root == NULL)
      root = temp;
   else {
      while(t != NULL) {
         if(t->d < d) {
            if(t->right == NULL) {
               t->right = temp;
               break;
            }
            t = t->right;
         } else if(t->d > d) {
            if(t->left == NULL) {
               t->left = temp;
               break;
            }
            t = t->left;
         }
      }
   }
   return root;
}
void Search(node *root, int d) {
   int depth = 0;
   node *temp = new node;
   temp = root;
   while(temp != NULL) {
      depth++;
      if(temp->d == d) {
         cout<<"\nitem found at depth: "<<depth;
         return;
      } else if(temp->d > d)
         temp = temp->left;
         else
            temp = temp->right;
   }
   cout<<"\n item not found";
   return;
}
int main() {
   char ch;
   int n, i, a[10] = {93, 53, 45, 2, 7, 67, 32, 26, 71, 76};
   node *root = new node;
   root = NULL;
   for (i = 0; i < 10; i++)
      root = InsertIntoTree(root, a[i]);
   up:
   cout<<"\nEnter the Element to be searched: ";
   cin>>n;
   Search(root, n);
   cout<<"\n\n\tDo you want to search more...enter choice(y/n)?";
   cin>>ch;
   if(c == 'y' || c == 'Y')
      goto up;
   return 0;
}

出力

Enter the Element to be searched: 26
item found at depth: 7
Do you want to search more...enter choice(y/n)?
Enter the Element to be searched: 1
item not found
Do you want to search more...enter choice(y/n)?