From c56064371977ec8d1f26e3afa6dba7c3f5c22367 Mon Sep 17 00:00:00 2001
From: technisRahulk <42281303+technisRahulk@users.noreply.github.com>
Date: Sat, 24 Oct 2020 02:02:26 +0530
Subject: [PATCH] Create Merge_K_sorted_Linked_Lists.cpp

Divide and conquer approach
---
 .../Merge_K_sorted_Linked_Lists.cpp           | 38 +++++++++++++++++++
 1 file changed, 38 insertions(+)
 create mode 100644 Data Structures/Linked List/Linear Linked List/Merge_K_sorted_Linked_Lists.cpp

diff --git a/Data Structures/Linked List/Linear Linked List/Merge_K_sorted_Linked_Lists.cpp b/Data Structures/Linked List/Linear Linked List/Merge_K_sorted_Linked_Lists.cpp
new file mode 100644
index 0000000..933e455
--- /dev/null
+++ b/Data Structures/Linked List/Linear Linked List/Merge_K_sorted_Linked_Lists.cpp	
@@ -0,0 +1,38 @@
+class Solution {
+private:
+      ListNode*merge(ListNode*a,ListNode*b){
+        ListNode*res=NULL;
+        if(a==NULL){
+            return b;
+        }
+        else if(b==NULL){
+            return a;
+        }
+        if(a->val<=b->val){
+            res=a;
+            res->next=merge(a->next,b);
+        }
+        else{
+           res=b;
+           res->next=merge(a,b->next); 
+        }
+        return res;
+    }
+    ListNode*utils(vector<ListNode*>& lists,int s,int e){
+        if(s==e){
+            return lists[s];
+        }
+        int mid=(s+e)/2;
+        ListNode*m1=utils(lists,s,mid);
+        ListNode*m2=utils(lists,mid+1,e);
+        return merge(m1,m2);
+    }
+public:
+    ListNode* mergeKLists(vector<ListNode*>& lists) {
+        if(lists.size()==0||(lists[0]==NULL&&lists.size()==1 ))
+            return NULL;
+        ListNode*res=NULL;
+        res=utils(lists,0,lists.size()-1);
+        return res;
+    }
+};