Subtree of Another Tree

This problem check if a certain part of a tree is same tree as a given subtree.

So before we solve this problem, we need to know how to check if two trees are same.

IsSameTree algo

Fundamentally, we need to check a certain part of a tree and see if it is same as the given sub-root.

1. write isSameTree Algo
2. Check if root, subTree is subtree of one another.
3. else move the root tree to left sub tree
4. else move the root tree to right sub tree.

isSameTree(p, q) {
if (!p && !q) {
  return true
}
if (!p || !q) {
   return false
}
if (p.val !== q.val) {
   return false
 }
return this.isSameTree(p.left, q.left) && this.isSameTree(p.right, q.right)

}

isSubtree(root, subRoot) {
         if(!subRoot){
            return true
         }
         if(!root){
            return false
         }
         if(this.isSameTree(root, subRoot)){
            return true
         }

return this.isSubtree(root.left, subRoot) || this.isSubtree(root.right,subRoot)

    }