Deleting a node by key from Singly linked list

Author: sudesh1611

Data Structures/SinglyLinkedList/Deletion_By_Key.c

@@ -0,0 +1,83 @@
+// A complete working C program to demonstrate deletion in singly 
+// linked list gien the key to delete
+#include <stdio.h> 
+#include <stdlib.h> 
+  
+// A linked list node 
+struct Node 
+{ 
+    int data; 
+    struct Node *next; 
+}; 
+  
+/* Given a reference (pointer to pointer) to the head of a list 
+   and an int, inserts a new node on the front of the list. */
+void push(struct Node** head_ref, int new_data) 
+{ 
+    struct Node* new_node = (struct Node*) malloc(sizeof(struct Node)); 
+    new_node->data  = new_data; 
+    new_node->next = (*head_ref); 
+    (*head_ref)    = new_node; 
+} 
+  
+/* Given a reference (pointer to pointer) to the head of a list 
+   and a key, deletes the first occurrence of key in linked list */
+void deleteNode(struct Node **head_ref, int key) 
+{ 
+    // Store head node 
+    struct Node* temp = *head_ref, *prev; 
+  
+    // If head node itself holds the key to be deleted 
+    if (temp != NULL && temp->data == key) 
+    { 
+        *head_ref = temp->next;   // Changed head 
+        free(temp);               // free old head 
+        return; 
+    } 
+  
+    // Search for the key to be deleted, keep track of the 
+    // previous node as we need to change 'prev->next' 
+    while (temp != NULL && temp->data != key) 
+    { 
+        prev = temp; 
+        temp = temp->next; 
+    } 
+  
+    // If key was not present in linked list 
+    if (temp == NULL) return; 
+  
+    // Unlink the node from linked list 
+    prev->next = temp->next; 
+  
+    free(temp);  // Free memory 
+} 
+  
+// This function prints contents of linked list starting from  
+// the given node 
+void printList(struct Node *node) 
+{ 
+    while (node != NULL) 
+    { 
+        printf(" %d ", node->data); 
+        node = node->next; 
+    } 
+} 
+  
+/* Drier program to test above functions*/
+int main() 
+{ 
+    /* Start with the empty list */
+    struct Node* head = NULL; 
+  
+    push(&head, 7); 
+    push(&head, 1); 
+    push(&head, 3); 
+    push(&head, 2); 
+  
+    puts("Created Linked List: "); 
+    printList(head); 
+    deleteNode(&head, 1); 
+    puts("\nLinked List after Deletion of 1: "); 
+    printList(head); 
+    return 0; 
+}