Given a non-negative integer represented in the form of a numeric string str. Remove zero or more characters from the string such that the number becomes divisible by 8. If it is possible, print the string after removing the characters otherwise print -1.
Input: str = “3454”
After removing ‘5’, string becomes 344 which is divisible by 8.
Input: str = “111”
Approach: Considering the divisibility rule of 8, we just need to check if the number formed by last 3 characters of str is divisible by 8 or not. Thus, we can iterate over all multiples of 8 upto 1000 and check if any of the multiple exists as a sub-sequence in the given string, then that multiple is our required answer. Otherwise, there exists no answer since all multiples of 8 greater than 1000 also needs to have the number (formed from last 3 digits) which has already been checked.
Below is the implementation of the above approach:
- Remove even frequency characters from the string
- Remove characters from string that appears strictly less than K times
- Extract maximum numeric value from a given string | Set 1 (General approach)
- Permutation of a string with maximum number of characters greater than its adjacent characters
- How to get the last n characters of a PHP string?
- How to remove the first character of string in PHP?
- Remove new lines from string in PHP
- Program to remove consonants from a String
- Iterate over characters of a string in Python
- Add index to characters and reverse the string
- Largest sub-string where all the characters appear at least K times
- Number of subsequences in a string divisible by n
- String with frequency of characters in Lucas Sequence
- Convert List of Characters to String in Java
- Python | Check if frequencies of all characters of a string are different
If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to firstname.lastname@example.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.
Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.