algorithm Binary Search Trees Lowest common ancestor in a BST
Example
Consider the BST:
Lowest common ancestor of 22 and 26 is 24
Lowest common ancestor of 26 and 49 is 46
Lowest common ancestor of 22 and 24 is 24
Binary search tree property can be used for finding nodes lowest ancestor
Psuedo code:
lowestCommonAncestor(root,node1, node2){
if(root == NULL)
return NULL;
else if(node1->data == root->data || node2->data== root->data)
return root;
else if((node1->data <= root->data && node2->data > root->data)
|| (node2->data <= root->data && node1->data > root->data)){
return root;
}
else if(root->data > max(node1->data,node2->data)){
return lowestCommonAncestor(root->left, node1, node2);
}
else {
return lowestCommonAncestor(root->right, node1, node2);
}
}
