Added solution for binary tree path sum problem hackdartstorm#1080

Author: Osamsami

exercises/1000_programs/medium/1080_insufficient_nodes_path_sum.py

@@ -0,0 +1,19 @@
+def hasPathSum(root, targetSum):
+    """
+    Determine if tree has root-to-leaf path with target sum.
+    This logic is fundamental for Decision Trees in Machine Learning.
+    """
+    # Base Case: Agar tree khali hai
+    if not root:
+        return False
+    
+    # Check if we are at a leaf node (node with no children)
+    if not root.left and not root.right:
+        # Check if the remaining sum matches the current node's value
+        return root.val == targetSum
+    
+    # Recursive step: Subtract current node's value from targetSum
+    # and search in children subtrees
+    remaining_sum = targetSum - root.val
+    
+    return hasPathSum(root.left, remaining_sum) or hasPathSum(root.right, remaining_sum)