/C++/Give an algorithm for finding the ith-to-last node in a singly linked list in which the last node is indicated by a null next reference.

Give an algorithm for finding the ith-to-last node in a singly linked list in which the last node is indicated by a null next reference.

LinkedListNode nthToLast(LinkedListNode head, int n) {
  if (head == null || n < 1) {
    return null;
  }

  LinkedListNode p1 = head;
  LinkedListNode p2 = head;

  for (int j = 0; j < n - 1; ++j) { // skip n-1 steps ahead
    if (p2 == null) {
      return null; // not found since list size < n
    }
    p2 = p2.next;
  }

  while (p2.next != null) {
    p1 = p1.next;
    p2 = p2.next;
  }

  return p1;
}

Source: stackoverflow.com

Similar codes

0 vote125 views1 answer
C++ x y in arrau 1d
C++
0 vote127 views1 answer
Run c++ program in mac terminal
C++
1 vote123 views1 answer
Taking a vector in c++ containing element
C++
0 vote128 views1 answer
Inverse Square
C++
0 vote121 views1 answer
Random 1 diem tren man hinh bang dev c
C++
3 votes122 views1 answer
C++ check if string is empty
C++
22 votes137 views4 answers
Getline cpp
C++
0 vote112 views1 answer
C++ convert integer to digits, as vector
C++
1 vote142 views1 answer
Vector remove class
C++
38 votes101 views10 answers
Convert whole string to lowercase c++
C++