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Lecture 29 - Test Review

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As usual, create a directory to hold today's activities:

  $ mkdir ~/cs170/labs/lab29 
  $ cd ~/cs170/labs/lab29

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1. Write a function called bool isPalindrome(char * a_string), which takes a single string as a parameter. Your function should return True if the parameter string is a palindrome.

   A string is a palindrome if its first and last letters are the same, and the string without the first and last letters is a palindrome. Notice that a string of length \(\leq 1\) is always a palindrome.

   YOU MAY NEED TO WRITE HELPER FUNCTIONS FOR THIS.

   palindrome.cc

   #include <iostream>
   using namespace std;
   
   void printBool(bool val) {
     if (val) {
       cout << "true" << endl;
     } else {
       cout << "false" << endl;
     }
   }
   /* Your code here */
   int main() {
     printBool(isPalindrome("bob"));      //true
     printBool(isPalindrome("racecar"));  //true
     printBool(isPalindrome("racecars")); //false
   }
   
   

2. Download the files LinkedList.h and LinkedList.cc into your directory. Create a new method of the Linked List class called void doubleList(). This method takes no parameters. It should create a duplicate of every node in the linked list. Partial credit will be awarded for an \(O(n^2)\) algorithm, full credit for an \(O(n)\) algorithm.

     LinkedList ls;
     /* some code which puts elements into the list */
   
     cout << ls << endl; //[1, 2, 3, 4]
     ls.doubleList();
     cout << ls << endl; //[1, 2, 3, 4, 1, 2, 3, 4]
   

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