Depth first traversal can be accomplished with an array and unshift, breadth-first search via an array and push. Following pseudo-code converts to a flat list:

# -*- pseudo-mode -*-
traverse_queue = [ root ];
work_queue = [];

while ( work_queue is_not empty ) {
    node = shift( traverse_queue );

    push( work_queue, node ) if BFS;

    push/unshift( traverse_queue, children );

    push( work_queue, node ) if DFS;
}
[download]