Add depth first search graph algo

Signed-off-by: Darko Draskovic <[email protected]>

src/algorithms/graph.js

@@ -0,0 +1,53 @@
+const g_connected = [
+ [2, 6, 10], // 0
+ [3, 7, 8, 9], // 1
+ [0, 3, 6], // 2
+ [1, 2, 4, 6], // 3
+ [3, 5], // 4
+ [4, 11], // 5
+ [0, 2, 3], // 6
+ [1, 8], // 7
+ [7, 1], // 8
+ [1], // 9
+ [0], // 10
+ [5], // 11
+]
+
+const g_disconnected = [
+ [2, 6, 10], // 0
+ [7, 8, 9], // 1
+ [0, 3, 6], // 2
+ [2, 6], // 3
+ [3, 5], // 4
+ [4, 11], // 5
+ [0, 2, 3], // 6
+ [1, 8], // 7
+ [7, 1], // 8
+ [1], // 9
+ [0], // 10
+ [5], // 11
+]
+
+function _dfs_visit(node, graph, visited) {
+ visited[node] = true;
+ graph[node].forEach(neighbor => {
+ if (!visited[neighbor]) _dfs_visit(neighbor, graph, visited);
+ });
+}
+
+function dfs(graph) {
+ let count = 0;
+ let visited = Array(graph.length).fill(false);
+ for (let i = 0; i < graph.length; i++) {
+ if (!visited[i]) {
+ count++;
+ _dfs_visit(i, graph, visited);
+ }
+ }
+ return count;
+}
+
+(function () {
+ dfs(g_connected);
+ dfs(g_disconnected);
+})()