/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

4 votes108 views2 answers
Float to int c++
C++
0 vote110 views1 answer
C++ do every 1 minutes
C++
1 vote102 views1 answer
Goto c++
C++
0 vote109 views1 answer
Simple program for sign in and sign up in c++
C++
0 vote115 views1 answer
Syntax of member function in c++
C++
0 vote165 views1 answer
C++ put a function in a other thread
C++
0 vote102 views1 answer
Access first value in a set c++
C++
1 vote98 views1 answer
64 bit unsigned integer c++
C++
0 vote104 views1 answer
. The cout with the insertion operator (<<) is used to print a statement
C++
1 vote101 views1 answer
Naive pattern matching algorithm
C++