Check if Binary tree is Sum tree or not | Love Babbar DSA Sheet | Amazon | Adobe 🔥 | GFG

[@coderaky]

bool res=true; int f(Node* root){ if(!root)return 0; int l=f(root->left); int r=f(root->right); if(!root->left && !root->right)return root->data; if(root->data!=l+r)res=false; return l+r+root->data; } bool isSumTree(Node* root) { res=true; f(root); return res; }

[@iztebah8118]

We can return if (a+b != root->data). As we already found the solution no need to further iterate.

[@dhruv2014]

Nice code and easy to understand 🔥🔥

[@divyanshuchaudhari5416]

if (f==0):return 0 is not required.In every recursive call it is checking this condition even before node condition is checked.So,no use. Otherwise great explanation bro..Keep going.

[@rajatmaheshwari4656]

also f = 1 in bool not req, just a global var is sufficient

[@rogeliojaylon4477]

So Nice 💘💘💘💘💘💘

[@nirajdas1331]

+1 for elegant solution

[@hiteshusingh8571]

Good Explanation!

[@sandipan_c]

There's no need to continue further if we see that, sum of leaves and its root is not equal. Python code is attached below. def recur(node): nonlocal flag if node is None: return 0 if node.left is None and node.right is None: return node.data else: sl = recur(node.left) sr = recur(node.right) if sl == -1 or sr == -1: return -1 if sl+sr != node.data: return -1 return sl + sr + node.data p = recur(root) return 0 if p == -1 else 1

[@kunalverma9777]

brute->better->optimal only discussing code is not helpful at all

[@akashchanabasanavar3031]

Is this code pass the case???

[@ankur420ify]

solution not working for all corner cases.

[@sainisaab684]

how to detrermine stack of tree is used or not!!???

[@BACSShaileshShettar]

the code provided in video is wrong. below is correct code. class Solution { boolean isSumTree(Node root) { boolean[] ans=new boolean[1]; ans[0]=true; int res=recurse(root,ans); return ans[0]; } static int recurse(Node root,boolean[] ans) { if (root==null) return 0; int left=recurse(root.left,ans); int right=recurse(root.right,ans); int sum=left+right; if (sum!=root.data && sum!=0) ans[0]=false; root.data+=sum; //System.out.println(root.data); return root.data; } }

[@mastersk7440]

Sare topic ka basic ka bad question karwaya

[@aishwaryajaiswal4720]

I wrote the same code and it's not working

[@akshaytak7775]

Maybe you globally initialized f =1, due to which your function is always returning true.

[@Viralmems_xyz]

bakbass explain

[@mastersk7440]

Bhai basic se karwoa yar

[@luffyy8084]

62 16 15 N 8 4 7 N 8 4 for this input gfg is saying output is wrong..can anyone help why this code doesnt work for this input?

[@akashjaiswal6478]

check after sometime it will give correct solution

[@samarthbhasin1204]

yess