add DFS algorithm

Algorithms-using-java/DFS/DFS.java

@@ -0,0 +1,48 @@
+public class DFS {
+    private static final int V = 8;
+
+    //	Adjacency Matrix for a Sample Graph
+    private static final int[][] GRAPH = {
+            //	       A  B  C  D  E  F  G  H
+            /*	A */ {0, 1, 1, 1, 0, 0, 0, 0},
+            /*	B */ {1, 0, 0, 0, 1, 1, 0, 0},
+            /*	C */ {1, 0, 0, 1, 0, 0, 0, 0},
+            /*	D */ {1, 0, 0, 1, 0, 0, 1, 0},
+            /*	E */ {0, 1, 1, 1, 0, 0, 0, 1},
+            /*	F */ {0, 1, 0, 0, 0, 0, 0, 1},
+            /*	G */ {0, 0, 0, 1, 0, 0, 0, 1},
+            /*	H */ {0, 0, 0, 0, 1, 1, 1, 0}
+    };
+    private static final int GRAPH_ROOT = 0;
+
+    // to keep track of visited node
+    private static final boolean[] VERTEX_VISITED = new boolean[V];
+
+    public static void DFS(int v) {
+
+        VERTEX_VISITED[v] = true;
+        System.out.println("Visited V" + v);
+
+        for (int u = 0; u < V; u++) {
+
+            // check for an edge between u and v
+            if (GRAPH[u][v] == 1) {
+                // check if this has been visited already
+                if (!VERTEX_VISITED[u]) {
+                    DFS(u);
+                }
+            }
+        }
+    }
+
+    public static void main(String[] s) {
+
+        for (int v = 0; v < V; v++) {
+            // set all vertices to NOT_VISITED
+            VERTEX_VISITED[v] = false;
+        }
+
+        System.out.println("\nDFS Traversal ::\n");
+        DFS(GRAPH_ROOT);
+    }
+}