fib.series.cpp

fib_series.cpp

@@ -0,0 +1,17 @@
+//Code to print Fibonacci Series issue#25
+#include <iostream>  
+using namespace std;  
+int main() {  
+  int n1=0,n2=1,n3,i,number;    
+ cout<<"Enter the number of elements: ";    
+ cin>>number;    
+ cout<<n1<<" "<<n2<<" "; //printing 0 and 1    
+ for(i=2;i<number;++i) //loop starts from 2 because 0 and 1 are already printed    
+ {    
+  n3=n1+n2;    
+  cout<<n3<<" ";    
+  n1=n2;    
+  n2=n3;    
+ }    
+   return 0;  
+   }  

fib_series2.cpp

@@ -0,0 +1,27 @@
+#include<stdio.h>
+int f(int);
+
+int main()
+{
+  int n, i = 0, c;
+
+  scanf("%d", &n);
+
+  printf("Fibonacci series terms are:\n");
+
+  for (c = 1; c <= n; c++)
+  {
+    printf("%d\n", f(i));
+    i++;
+  }
+
+  return 0;
+}
+
+int f(int n)
+{
+  if (n == 0 || n == 1)
+    return n;
+  else
+    return (f(n-1) + f(n-2));
+}

linked_list.cpp

@@ -0,0 +1,105 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+typedef struct node {
+    int data;
+    struct node* next;
+} node;
+
+void insert_node(node** head, int val, int position);
+
+void insert_node(node** head, int val, int position)
+{
+    struct node *curr = *head, *tmp_node = NULL;
+    int count = 1;
+
+    tmp_node = (node*)malloc(sizeof(node));
+
+    if (tmp_node == NULL) {
+        printf("Memory allocation is failed:");
+        return;
+    }
+    tmp_node->data = val;
+    tmp_node->next = NULL;
+
+    if (*head == NULL) {
+        // List is empty, assigning head pointer to tmp_node
+        *head = tmp_node;
+        return;
+    }
+    if (position == 1) {
+        // Inserting node at the beginning of the list
+        tmp_node->next = *head;
+        *head = tmp_node;
+        return;
+    }
+    while (curr && count < position - 1) {
+        curr = curr->next;
+        count++;
+    }
+    if (position > (count + 1)) {
+        printf("\n position doesn't exists in the list ");
+        return;
+    }
+    if (count + 1 == position && curr->next == NULL) {
+        // Inseting node at the end of the list
+        curr->next = tmp_node;
+        return;
+    }
+    // Inserting node in the list at given position
+    tmp_node->next = curr->next;
+    curr->next = tmp_node;
+}
+
+void print_list(node* head)
+{
+    printf("\nList elements:\n");
+    while (head) {
+        printf("%d ", head->data);
+        head = head->next;
+    }
+    printf("\n");
+    return;
+}
+
+int main()
+{
+    int num_nodes, value, index, position;
+    node* head = NULL;
+
+    printf("Enter the no. of nodes to create list: ");
+    scanf("%d", &num_nodes);
+
+    for (index = 1; index <= num_nodes; index++) {
+        printf("Enter node data for position %d in the list:  ", index);
+        scanf("%d", &value);
+        insert_node(&head, value, index);
+    }
+    print_list(head);
+
+    printf("\nInsert the element at 1st position:  ");
+    scanf("%d", &value);
+    insert_node(&head, value, 1);
+    // We have inserted one more element, hence num_nodes get increased by 1
+    num_nodes += 1;
+    print_list(head);
+
+    printf("\nInsert the element at last position:  ");
+    scanf("%d", &value);
+    insert_node(&head, value, num_nodes + 1);
+    // We have inserted one more element, hence num_nodes will get increased by 1
+    num_nodes += 1;
+    print_list(head);
+
+    printf("\nInsert the element at any position in the list\n");
+    printf("Enter the position: ");
+    scanf("%d", &position);
+    printf("Enter the element value: ");
+    scanf("%d", &value);
+    insert_node(&head, value, position);
+    // We have inserted one more element, hence num_nodes will get increased by 1
+    num_nodes += 1;
+    print_list(head);
+
+    return 0;
+}