/* 0 is white, 1 is gray, 2 is black */
global color = int[]{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}; 
global startTimes = int[]{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
global finishTimes = int[]{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
global topoSort = int[]{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
global numVertices = 16;
global index = 15;

void dfs(int[][] adj) {
	
	for (var i = 0; i < numVertices; i=i+1;) {
		if (color[i] == 0) {
			dfsHelper(adj, i, 0);
		}
	}
	return;
}

void dfsHelper(int[][] adj, int s, int t) {
	color[s] = 1;
	startTimes[s] = t;

	var stringRep = string_of_array(adj[s]);
	var length = length_of_string(stringRep);

	for (var i = 0; i < length; i=i+1;) {
		var neighbor = adj[s][i];
		if (color[neighbor] == 0) {
			dfsHelper(adj, neighbor, t + 1);
		}
	}

	color[s] = 2;
	finishTimes[s] = t + 1;
	topoSort[index] = s;
	index = index - 1;

	return;
}

int program(int argc, string[] argv) {
	/* Graph taken from https://i.stack.imgur.com/zuLmn.png */
	var adjList = new int[][]{new int[]{7, 10, 13, 14}, new int[]{2, 9, 13}, new int[]{10, 12, 13, 14}, new int[]{6, 8, 9, 11}, new int[]{7}, new int[]{6, 7, 9, 10}, new int[]{15}, new int[]{14}, new int[]{15}, new int[]{11, 14}, new int[]{14}, new int[]{}, new int[]{}, new int[]{}, new int[]{}, new int[]{}};
	dfs(adjList);
	for (var i = 0; i < numVertices; i=i+1;) {
		print_int(topoSort[i]);
		print_string (" ");
	}
	print_string ("-");
	return 0;
}