A network of n nodes labeled $1$ to $n$ is provided along with a list of travel times for directed edges represented as $times[i]=(x_i​, \space y_i​, \space t_i​)$, where $x_i$​ is the source node, $y_i$​ is the target node, and $t_i$​ is the delay time from the source node to the target node.

Considering we have a starting node, k, we have to determine the minimum time required for all the remaining for n - 1 nodes to receive the signal. Return $-1$ if it is not possible for all n - 1 nodes to receive the signal.

Constraints:

• $1 \leq$ k $\leq$ n $\leq$