DSA-LEARNING-PROGRESS/LL-Reverse.cpp at main · Manya0209/DSA-LEARNING-PROGRESS · GitHub

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#include<iostream>
using namespace std;

void reverse(Node* &head, Node* curr, Node* prev){
    if(curr==NULL){
        head= prev;
        return ;
    }
    Node* forward = curr->next;
    reverse(head, curr, prev);
    curr->next= prev;
}

Node* reverseLinkedList(Node* head){
    //Approach 1
    // if(head==NULL || head->next==NULL){
    //     return head;
    // }
    // Node* prev= NULL;
    // Node* curr= head;
    // Node* forward= NULL;

    // while(curr != NULL){
    //     forward= curr->next ;
    //     curr->next= prev;
    //     prev= curr;
    //     curr= forward;
    // }

    // return prev;


    //Approach 2
    Node* curr= head;
    Node* prev= NULL;
    reverse(head, curr, prev);
    return head;
}

int main(){

}