[LeetCode] Validate Binary Search Tree in Objective C

LeetCode: Validate Binary Search Tree in Objective C

typedef struct {
    int value;
    struct TreeNode *left;
    struct TreeNode *right;
 } TreeNode;

-(BOOL)isValidBST:(TreeNode *)node
{
   return (valid:node minValue:INT_MIN maxValue:INT_MAX);
}

-(BOOL)valid:(TreeNode *)treeNode minValue:(int)minValue maxValue(int)max
{
  if (!treeNode) return true;
  return treeNode.value > minValue && treeNode.value < maxValue
    && (valid:treeNode.left, minValue, treeNode.value) 
    && (valid:treeNode.right, treeNode.value, maxValue) 
}