algorythms
Tree DFS
LC #112Easy

Path Sum

Tree DFS
AmazonGoogleMicrosoft

Problem

Determine if the tree has a root-to-leaf path that sums to target.

treedfs

Constraints

  • 0 ≤ n ≤ 5000
  • -1000 ≤ Node.val ≤ 1000
  • -1000 ≤ targetSum ≤ 1000

Example

Inputroot = [5, 4, 8, 11, null, 13, 4, 7, 2, null, null, null, 1], targetSum = 22
Outputtrue
Why

Path 5→4→11→2 = 22

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