Algorithm to print all paths with a given sum in a binary tree

Question

The following is an interview question.

You are given a binary tree (not necessarily BST) in which each node contains a value. Design an algorithm t

Answer 1

// assumption node have integer value other than zero
void printAllPaths(Node root, int sum , ArrayList path) {

   if(sum == 0) {
      print(path); // simply print the arraylist
    }

   if(root ==null) {
     //traversed one end of the tree...just return
      return;
  }
    int data = root.data;
    //this node can be at the start, end or in middle of path only if it is       //less than the sum
    if(data<=sum) {
     list.add(data);
     //go left and right
    printAllPaths(root.left, sum-data ,  path);
    printAllPaths(root.right, sum-data ,  path);

    }
   //note it is not else condition to ensure root can start from anywhere
   printAllPaths(root.left, sum ,  path);
   printAllPaths(root.right, sum ,  path);
}