Node *commonAncestor(Node *root, Node *node1, Node *node2) {
if (root == nullptr || node1 == nullptr || node2 == nullptr) return nullptr;
if (find(root->left, node1) && find(root->left, node2))
return commonAncestor(root->left, node1, node2);
else if (find(root->right, node1) && find(root->right, node2))
return commonAncestor(root->right, node1, node2);
else
return root;
}
int main(){
struct node *root = NULL;
add(&root,4);
add(&root,1);
add(&root,3);
add(&root,7);
add(&root,9);
add(&root,5);
add(&root,8);
add(&root,2);
add(&root,6);
struct node *b = NULL;
add(&b,1);
add(&b,2);
add(&b,3);
add(&b,4);
add(&b,5);
add(&b,6);
add(&b,7);
add(&b,8);
add(&b,9);
printf("\n\n Compare trees for similarity: %s \n\n", isSimilar(root,b) ? "true": "false");
printf("\n\ninorder:");
inorder(root);
// printf("\nPREORDER: \n");
// preorderStack(root);
printf("\nPOSTORDER: \n");
postOrderStack(root);
struct node *lca_6_8 = commonAncestor(root,find(root,8),find(root,6));
printf("\n\nleast common ancestor: 6,8: %d\n", lca_6_8->data);
struct node *lca_2_8 = commonAncestor(root,find(root,8),find(root,2));
printf("\n\nleast common ancestor: 2,8: %d\n", lca_2_8->data);
struct node *lca_6_7 = commonAncestor(root,find(root,7),find(root,6));
printf("\n\nleast common ancestor: 6,7: %d\n", lca_6_7->data);
int distance_6_8 = distance(root,find(root,8),find(root,6));
printf("\n\ndistance: 6,8: %d\n", distance_6_8);
int distance_2_8 = distance(root,find(root,8),find(root,2));
printf("\n\ndistance: 2,8: %d\n", distance_2_8);
int distance_6_7 = distance(root,find(root,7),find(root,6));
printf("\n\ndistance: 6,7: %d\n", distance_6_7);
printf("\n\nzigazag:");
zigzag(root);
printf("\n\n");
}
struct node* commonAncestor(struct node *root, struct node *a, struct node *b){
if(root == NULL){
return NULL;
}
struct node *t1 = commonAncestor(root->left,a,b);
struct node *t2 = commonAncestor(root->right,a,b);
struct node *t3 = root == a || root ==b ? root : NULL;
int sum = (t1 == NULL ? 0 : 1) + (t2 == NULL ? 0 : 1) + (t3 == NULL ? 0 : 1);
if(sum == 2)
return root;
return t1 != NULL ? t1 : (t2 != NULL ? t2 : t3);
}