Sum of Last N nodes of the Linked List added

Sum of Last N nodes of the Linked List.cpp

@@ -0,0 +1,92 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+struct node{
+    int data;
+    struct node *next;//
+}*head;
+
+void insertq(int a[],int m){
+    struct node *temp,*newnode;
+    head=(struct node*)malloc(sizeof(struct node));//
+
+    head->data=a[0];
+    head->next=NULL;
+
+   // temp=(struct node*)malloc(sizeof(struct node));;
+    temp=head;
+    //head->next=temp;
+
+    for(int i=1;i<m;i++){
+       newnode = (struct node*)malloc(sizeof(struct node));//
+        newnode->data=a[i];
+        newnode->next=NULL;
+
+        temp->next=newnode;
+       // newnode=newnode->next;
+        temp=newnode;
+    }
+
+
+}
+void printq(struct node *head){
+
+    struct node*temp;
+    temp=head;
+    while(temp!=NULL){
+        cout<<temp->data<<"\n";
+        temp=temp->next;
+    }
+}
+
+
+int sumOfLastN_Nodes(struct node* head, int n)
+{
+      // Code here
+      if(n<=0)
+        return 0;
+      struct node*temp = head;
+      int m=0,sum=0;
+      while(temp!=NULL){
+          m++;
+          temp=temp->next;
+      }
+    cout<<"m...."<<m<<endl;
+     temp = head;
+      for(int pos=1;pos<m-n+1;pos++){
+          temp=temp->next;
+          cout<<"head\n"<<"....."<<temp->data<<endl;
+      }
+
+      while(temp!=NULL){
+          sum+=temp->data;
+          cout<<"sum  here,,,"<<sum<<endl;
+          temp=temp->next;
+      }
+      cout<<"sum\n"<<"....."<<sum<<endl;
+      return sum;
+}
+
+
+int main(){
+
+    int m;
+    cout<<"enter size\n";
+    cin>>m;
+    int a[m];
+    cout<<"enter elements\n";
+    for(int i=0;i<m;i++){
+        cin>>a[i];
+    }
+    cout<<"enter nth\n";
+    int n;
+    cin>>n;
+    cout<<"calling insert....\n";
+    insertq(a,m);
+    cout<<"calling print....\n";
+    printq(head);
+    int res=sumOfLastN_Nodes(head,n);
+    cout<<"print sum....\n"<<res;
+return 0;
+}
+