Commit cc22876

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added 143.Reorder_List.cpp using cpp , 95.98% faster (#183)

* Create 143.Reorder_List.cpp * readme

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Original file line number	Diff line number	Diff line change
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	`1`	`+/* medium difficulty */`
	`2`	`+`
	`3`	`+class Solution {`
	`4`	`+public:`
	`5`	`+ void reorderList(ListNode* head) {`
	`6`	`+`
	`7`	`+ //edge cases`
	`8`	`+ if ((!head) \|\| (!head->next) \|\| (!head->next->next)) return;`
	`9`	`+`
	`10`	`+ int l=0; //to calculate the length`
	`11`	`+ ListNode* curr=head;`
	`12`	`+ while(curr){`
	`13`	`+ l++;`
	`14`	`+ curr=curr->next;`
	`15`	`+ }`
	`16`	`+`
	`17`	`+ //stack to store the second half of the elements of the ll`
	`18`	`+ stack<ListNode*> s;`
	`19`	`+ curr=head;`
	`20`	`+`
	`21`	`+ //iterating till the end of the first half`
	`22`	`+ int m=(l+1)/2;`
	`23`	`+ while(m>=1){`
	`24`	`+ curr=curr->next;`
	`25`	`+ m--;`
	`26`	`+ }`
	`27`	`+`
	`28`	`+ //pushing the second half of the elements in the stack`
	`29`	`+ while(curr){`
	`30`	`+ s.push(curr);`
	`31`	`+ curr=curr->next;`
	`32`	`+ }`
	`33`	`+`
	`34`	`+ //attaching the elements from the top of the stack to the first half of the elements`
	`35`	`+ curr=head;`
	`36`	`+ while(curr&&!s.empty()){`
	`37`	`+ ListNode* temp=s.top();`
	`38`	`+ s.pop();`
	`39`	`+ temp->next=curr->next;`
	`40`	`+ curr->next=temp;`
	`41`	`+ curr=curr->next->next;`
	`42`	`+ }`
	`43`	`+ curr->next=NULL;`
	`44`	`+ }`
	`45`	`+};`

Lines changed: 3 additions & 1 deletion

Original file line number	Diff line number	Diff line change
`@@ -186,7 +186,9 @@ Check out ---> [Sample PR](https://github.com/codedecks-in/LeetCode-Solutions/pu`
`186`	`186`	`\| 142 \| [Linked List Cycle II](https://leetcode.com/problems/linked-list-cycle-ii/) \| [Java](./Java/linked-list-cycle-ii.java) <br> [C++](./C++/Linked-List-Cycle-II.cpp) \| _O(n)_ \| _O(1)_ \| Medium \| Slow-Fast Pointers \| \|`
`187`	`187`	`\| 146 \| [LRU Cache](https://leetcode.com/problems/lru-cache/) \| [C++](./C++/LRU-Cache.cpp) <br> [Python](./Python/LRUCache.py) \| _O(1)_ \| _O(k)_ \| Medium \| Hash Map \| \|`
`188`	`188`	`\| 160 \| [Intersection of Two Linked Lists](https://leetcode.com/problems/intersection-of-two-linked-lists/) \| [Java](./Java/intersection-of-two-linked-lists.java) \| _O(n)_ \| _O(1)_ \| Easy \| Two Pointers \| [Tutorial](https://youtu.be/uozGB0-gbvI) \|`
`189`		`-\| 186 \| [Middle of the Linked List](https://leetcode.com/problems/middle-of-the-linked-list/) \| [Java](./Java/middle-of-the-linked-list.java) \| _O(n)_ \| _O(1)_ \| Easy \| Two pointers \| \|`
	`189`	`+\| 186 \| [Middle of the Linked List](https://leetcode.com/problems/middle-of-the-linked-list/) \| [Java](./Java/middle-of-the-linked-list.java) \| _O(n)_ \| _O(1)_ \| Easy \| Two pointers \|`
	`190`	`+\| 143 \| [Reorder List](https://leetcode.com/problems/reorder-list/) \| [C++](./C++/143.Reorder_List.cpp) \| _O(n)_ \| _O(n)_ \| Medium \| Iteration and Stack \|`
	`191`	`+ \|`
`190`	`192`
`191`	`193`	`<br/>`
`192`	`194`	`<div align="right">`

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