Question

Rearrange the following algorithm in the correct order to determine whether a string of n characters is a palindrome.

Rank the options below.
answer = false
if ajan +1-¡then answer = false
i:=1
answer = true
procedure palindromecheck(a1, a2,... an: string)
i:=i+1
while (ajan +1-¡ and i < n/2)
return answer

Answer 1

To check if a string is a palindrome, arrange the algorithm steps methodically so that each character is compared with its symmetric counterpart. If any characters do not match, conclude the string is not a palindrome; otherwise, confirm it is.

Step-by-step explanation:

To determine whether a string of n characters is a palindrome, we need to rearrange the provided algorithm into a coherent procedure. A palindrome is a string that reads the same forwards and backwards. The correct order for the palindrome checking algorithm is as follows:

Palindrome Check Algorithm

1. procedure palindromecheck(a1, a2,... an: string)
2. answer = true
3. i:=1
4. while (i <= n/2)
5. if aj ≠ an +1-i then
6. answer = false
7. exit the while loop
8. i:=i+1
9. end while
10. return answer

In this algorithm, we initialize our answer to true and our index i to 1. We then check the characters of the string in a loop that runs until i exceeds n/2. If at any point the character ai is not equal to the character an + 1 - i (which is the character at the symmetric position from the end of the string), we set the answer to false and break out of the loop. If we complete the loop and no mismatches are found, the string is a palindrome and the answer remains true.