Form binary search tree structure and display the nodes level wise

A ‘C’ program to read ‘n’ integers and store them in a Binary search tree structure and display the nodes level wise.

Binary search tree source code

#include 

typedef struct node {
  int value;
  struct node * right;
  struct node * left;
}
mynode;

mynode * root;

void add_node(int value);

void levelOrderTraversal(mynode * root);

void main() {
  int num;
  char ch = ’y’;
  clrscr();
  root = NULL;
  do {
    printf(“\nenter the node value”);
    scanf(“ % d”, & num);
    add_node(num);
    printf(“\ndo you want to
      continue (y / n)”);
    flushall();
    scanf(“ % c”, & ch);
  } while (ch != ’n’);
  printf(“\n\ n\ nLEVEL ORDER TRAVERSAL\ n\ n”);
  levelOrderTraversal(root);

  getch();
}

// Function to add a new node…
void add_node(int value) {
  mynode * prev, * cur, * temp;

  temp = (mynode * ) malloc(sizeof(mynode));
  temp - > value = value;
  temp - > right = NULL;
  temp - > left = NULL;

  if (root == NULL) {
    printf(“\nCreating the root..\n”);
    root = temp;
    return;
  }

  prev = NULL;
  cur = root;

  while (cur != NULL) {
    prev = cur;
    cur = (value < cur - > value) ? cur - > left : cur - > right;
  }

  if (value < prev - > value)
    prev - > left = temp;
  else
    prev - > right = temp;
}

// Level order traversal..
void levelOrderTraversal(mynode * root) {
  mynode * queue[100] = {
    (mynode * ) 0
  }; // Important to initialize!
  int size = 0;
  int queue_pointer = 0;

  while (root) {
    printf(“[ % d]“, root - > value);

    if (root - > left) {
      queue[size++] = root - > left;
    }

    if (root - > right) {
      queue[size++] = root - > right;
    }

    root = queue[queue_pointer++];
  }
}

Output

enter the node value5

Creating the root..

do you want to continue (y/n)y

enter the node value7

do you want to continue (y/n)y

enter the node value3

do you want to continue (y/n)y

enter the node value10

do you want to continue (y/n)y

enter the node value2

do you want to continue (y/n)n

LEVEL ORDER TRAVERSAL

[5] [3] [7] [2] [10]