maximum path sum in a binary tree

maximum path sum in a binary tree.cpp

@@ -0,0 +1,67 @@
+
+#include<bits/stdc++.h> 
+using namespace std; 
+
+
+struct Node 
+{ 
+    int data; 
+    struct Node* left, *right; 
+}; 
+
+
+struct Node* newNode(int data) 
+{ 
+    struct Node* newNode = new Node; 
+    newNode->data = data; 
+    newNode->left = newNode->right = NULL; 
+    return (newNode); 
+} 
+
+
+int findMaxUtil(Node* root, int &res) 
+{ 
+
+    if (root == NULL) 
+        return 0; 
+
+
+    int l = findMaxUtil(root->left,res); 
+    int r = findMaxUtil(root->right,res); 
+
+
+    int max_single = max(max(l, r) + root->data, root->data); 
+
+
+    int max_top = max(max_single, l + r + root->data); 
+
+    res = max(res, max_top);  
+
+    return max_single; 
+} 
+
+
+int findMaxSum(Node *root) 
+{ 
+
+    int res = INT_MIN; 
+
+
+    findMaxUtil(root, res); 
+    return res; 
+} 
+
+
+int main(void) 
+{ 
+    struct Node *root = newNode(10); 
+    root->left        = newNode(2); 
+    root->right       = newNode(10); 
+    root->left->left  = newNode(20); 
+    root->left->right = newNode(1); 
+    root->right->right = newNode(-25); 
+    root->right->right->left   = newNode(3); 
+    root->right->right->right  = newNode(4); 
+    cout << "Max path sum is " << findMaxSum(root); 
+    return 0; 
+}