Incrementing timer after setting tout[v]. You should only increment after tin[v], not after tout[v]. Using tout[v] values that exceed .
All values should be bounded by since you only increment the timer times (once per node). Querying range [tin[v], tout[v]) but forgetting that only entry positions hold values.
Another common mistake: forgetting to handle the root's tout value. The root's tout should cover the entire array since its subtree is the full tree.