C Code of Leftist Tree

#include <stdio.h>
struct node
{
int data,dist;
struct node *right,*left,*prnt;

}*root,*temp,*root3,*root4;
void print(struct node *p)
{
if(p!=NULL)
{
print(p->left);
printf("\t%d",p->data);
print(p->right);
}
}

int distance(struct node *m)
{
if(m==NULL)
{
return(-1);
}
else
{
return(m->dist);
}
}
struct node * merg(struct node *a,struct node *b)
{
if(a==NULL)
return b;
if(b==NULL)
return a;
if(b->data>a->data)
{
temp=b;
b=a;
a=temp;
}
a->right=merg(a->right,b);
if(distance(a->right)>distance(a->left))
{
temp=a->right;
a->right=a->left;
a->left=temp;

}
if(a->right==NULL)
a->dist=0;
else
a->dist=1+(a->right->dist);
return(a);
}
struct node * deletion(struct node * root)
{
printf("deleted element is %d",root->data);
root=merg(root->right,root->left);
}
struct node * insert(struct node *root1)
{ int val;
struct node *newnode,*x;
newnode=(struct node *)malloc(sizeof(struct node));
newnode->right=NULL;
newnode->left=NULL;
newnode->dist=0;
newnode->prnt=NULL;
printf("\n enter value");
scanf("%d",&val);
newnode->data=val;
root1=merg(root1,newnode);
printf("root element is %d\n \n inorder traversal of tree is:",root->data);
print(root1);
return(root1);
}
void meld()
{
int val;
printf("\n1st tree:");
root3=(struct node *)malloc(sizeof(struct node));
root3->right=NULL;
root3->left=NULL;
root3->dist=0;
printf("\nenter 1st data");
scanf("%d",&val);
root3->data=val;
while(1)
{
printf("\ndo u waana insert element to 1st tree(0/1)");
scanf("%d",&val);
if(val)
{
root3=insert(root3);
}
else
break;
}

printf("\n2nd tree:");
root4=(struct node *)malloc(sizeof(struct node));
root4->right=NULL;
root4->left=NULL;
root4->dist=0;
printf("\nenter 1st data");
scanf("%d",&val);
root4->data=val;
while(1)
{
printf("\ndo u waana insert element to 1st tree(0/1)");
scanf("%d",&val);
if(val)
{
root4=insert(root4);
}
else
break;
}
printf("\n 1st tree");
print(root3);
printf("\n 2nd tree");
print(root4);
root3=merg(root3,root4);
printf("\nroot element is: %d\n",root3->data);
print(root3);
}
int main()
{ int fl=0,val;
printf("\n enter root node");
scanf("%d",&val);
root=(struct node *)malloc(sizeof(struct node));
root->right=NULL;
root->left=NULL;
root->dist=0;
root->data=val;
root->prnt=NULL;
while(1)
{
printf("\n enter ur option \n 1.insert 2.print 3.delete 4.meld 5.exit\n");
scanf("%d",&val);
switch(val)
{
case 1:
root=insert(root);
break;
case 2:
printf("\n");
print(root);
break;
case 3:
root=deletion(root);
break;
case 4:
meld();
break;
case 5:
fl=1;
break;
default:
break;

}
if(fl==1)
{
break;
}
}
}