Added C Implementation of DFS ( Issue jainaman224#160) (jainaman224#354)

* Added Depth First Search in c

* Added c implementation of DFS

* Made Required Changes

Author: sagar-bharadwaj-ks

Depth_First_Search/Depth_First_Search.c

@@ -0,0 +1,82 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+//Structure for each vertex in graph
+struct node
+{
+    int data;
+    struct node* next;
+};
+
+//Function to add node at the end of given root
+struct node* insert(struct node *root,int d)
+{
+    struct node *newPtr = (struct node*)malloc(sizeof(struct node));
+    newPtr->data = d;
+    newPtr->next = NULL;
+
+    root->next = newPtr;
+
+    return newPtr;
+}
+
+//Function to perform DFS
+void explore(int node,int vis[],struct node start[])
+{
+    printf("%d ",node);
+    vis[node]=1;
+
+    struct node *ptr = start[node].next;
+
+    for(;ptr!=NULL;ptr=ptr->next)
+    {
+        if(vis[ptr->data]==0)
+        {
+            explore(ptr->data,vis,start);
+        }
+    }
+}
+
+
+int main()
+{
+    int no_of_vertices = 7,i,vis[8];
+
+    struct node start[8];
+
+    for(i=1;i<=no_of_vertices;i++)
+    {
+        start[i].data=i;
+        start[i].next=NULL;
+        vis[i]=0;
+    }
+
+    /*
+    Creates the following graph :
+                 1
+               /   \
+              2     3
+             / \   / \
+            4   5 6   7
+    */
+    struct node *cur;
+    cur = insert(&start[1],2);
+    insert(cur,3);
+    cur = insert(&start[2],4);
+    insert(cur,5);
+    cur = insert(&start[3],6);
+    insert(cur,7);
+
+    //The loop takes care of non connected graph also
+    printf("DFS of the graph : \n");
+    for(i=1;i<=7;i++)
+    {
+        if(vis[i]==0)
+            explore(i,vis,start);
+    }
+
+    return 0;
+
+
+    // Output : 1 2 4 5 3 6 7
+}