Question

Here is an example of jumping out of a loop too early. The code below is intended to test if all of the letters in a string are in ascending order from left to right. But, it doesn’t work correctly. Can you fix it? Fix the code below so it does not leave the loop too early. Try the CodeLens button to see what is going on. When should you return true or false? p

Answer 1

The provided code attempts to check if letters in a string are in ascending order, but exits the loop too early. To fix this, iterate over each letter, checking if the current letter is greater than or equal to the previous one, and return False if not. Finally, return True if all letters pass the condition.

Step-by-step explanation:

The code provided is attempting to test if all the letters in a string are in ascending order from left to right. However, there is an issue with the logic that causes the code to exit the loop too early.

To fix the code, you need to iterate over each letter in the string and check if the current letter is greater than or equal to the previous letter. If at any point the condition is not satisfied, you should return False. Only if all the letters pass the condition, you can return True outside the loop.

def is_ascending(string):
for i in range(1, len(string)):
if string[i] <= string[i-1]:
return False
return True

Answer 2

Based on the above, the corrected code:

java

public class Loop3

{

public static boolean isInOrder(String check)

{

int pos = 0;

while (pos < check.length() - 1)

{

String letter1 = check.substring(pos, pos+1);

String letter2 = check.substring(pos+1, pos+2);

if (letter1.compareTo(letter2) >= 0)

{

return false; // Return false if any pair is not in ascending order

}

pos++;

}

return true; // If the loop completes without returning false, all letters are in ascending order

}

public static void main(String[] args)

{

System.out.println(isInOrder("abca") + " should return false");

System.out.println(isInOrder("abc") + " should return true");

}

}

The problem with the first code is that it says "true" as soon as it finds two letters in a row that go in order. This does not guarantee that all the letters in the string are in order from A to Z.

So, the above given corrected code makes sure that the loop completes its entire iteration, checking all pairs of adjacent letters before returning the final verdict.

See text below

Here is an example of jumping out of a loop too early. The code below is intended to test if all of the letters in a string are in ascending order from left to right. But, it doesn’t work correctly. Can you fix it? Fix the code below so it does not leave the loop too early. Try the CodeLens button to see what is going on. When should you return true or false? p

public class Loop3

{

public static boolean isInOrder(String check)

{

int pos = 0;

while (pos < check.length() - 1)

{

String letter1 = check.substring(pos, pos+1);

String letter2 = check.substring(pos+1, pos+2);

if (letter1.compareTo(letter2) < 0)

{

return true;

}

pos++;

}

return false;

}

public static void main(String[] args)

{

System.out.println(isInOrder("abca") + " should return false");

System.out.println(isInOrder("abc") + " should return true");

}

}