Data Structures: Depth-First Search

Data Structures/dfs.js

@@ -0,0 +1,25 @@
+// https://www.freecodecamp.org/learn/coding-interview-prep/data-structures/depth-first-search
+
+function dfs(graph, root) {
+  const n_nodes = graph[0].length;
+  const reachable = new Set([root]);
+  const stack = [root];
+  while (stack.length) {
+    const node = stack.pop();
+    for (let i = 0; i < n_nodes; i++) {
+      if (graph[node][i] > 0 && !reachable.has(i)) {
+        reachable.add(i);
+        stack.push(i);
+      }
+    }
+  }
+  return Array.from(reachable);
+}
+
+var exDFSGraph = [
+  [0, 1, 0, 0],
+  [1, 0, 1, 0],
+  [0, 1, 0, 1],
+  [0, 0, 1, 0],
+];
+console.log(dfs(exDFSGraph, 3));