Merge pull request #265 from monishamandal02/main

Convert Binary Number in a Linked List to Integer (LINKED LIST) #210

Linked List/C++/7_Convert Binary Number in a Linked List to Integer.cpp

@@ -0,0 +1,70 @@
+/*
+Problem: Binary to Linked list Integer.
+
+Description: Given head which is a reference node to a singly-linked list. 
+The value of each node in the linked list is either 0 or 1. 
+The linked list holds the binary representation of a number.
+Return the decimal value of the number in the linked list.
+*/
+
+#include <iostream>
+using namespace std;
+
+class ListNode
+{
+	public:
+	bool val;
+	ListNode* next;
+};
+
+int getDecimalValue(ListNode* head) //Returns decimal value of binary linked list
+    {
+        int ans = 0;
+        while(head != NULL)
+        {
+            ans = (ans*2) + head->val;
+            head = head->next;
+        }
+        return ans;
+    }
+ListNode *newNode(bool val) //function to create a new node
+{
+	ListNode *temp = new ListNode;
+	temp->val = val;
+	temp->next = NULL;
+	return temp;
+}
+
+int main()
+{
+	ListNode* head = newNode(1); //empty list
+	head->next = newNode(0);
+	head->next->next = newNode(1);
+	cout << "Decimal value is "
+		<< getDecimalValue(head);
+
+	return 0;
+}
+
+/*
+Input: head = 1->0->1
+Output: 5
+
+Example:
+If below examples are needed to be printed in drivers code we have to keep on adding ->next.
+Input: head = 1->0->0->1->0->0->1->1->1->0->0->0->0->0->0
+Output: 18880
+
+Input  : 0->0->0->1->1->0->0->1->0
+Output : 50
+
+Head: Head is the top most element. If the binary input is 101100 then 1 at left side will be considered as head.
+
+Explanation:
+(1011) base 2 = (1*2^3) + (0*2^2) + (1*2^1) + (1*2^0)
+let result be the last element:
+step 1: result = 1 = 1*2^0
+step 2: (result*2) + 0 = ((1*2^2 + 0) * 2 + 1)
+step 3:                = ((1*2^2 + 0*2^1 + 1*2^0) * 2)
+step 4:                = (1*2^3 + 0*2^2 + 1*2^1 + 1)
+*/