Challenge: Implement Depth First Graph Traversal

Problem Statement

Implement the Depth-First Traversal in C++.

Input

A graph represented as an adjacency list and a starting vertex (root).

Output

A string containing the vertices of the graph listed in the correct order of traversal.

Sample Input

Graph:

graph = {0 -> 1
         1 -> 2
         1 -> 3
         2 -> 4
         3 -> 4
         3 -> 5}

Sample Output

"0 1 2 4 3 5" or "0 1 2 4 3 5"