Find the longest substring ending in a specific string (with.Java)

This is a recap of the “Find the longest substring ending in a specific string” problem.

We’re going to look at it as a coding test problem, provide a retrospective on how we solved it, and explore other ways to solve it.

Let’s start with the problem

Problem

You are given the strings myString and pat.

Complete a solution function that finds and returns the longest substring of myString that ends in pat.

Example input and output

My solution to the problem

class Solution {
    public String solution(String myString, String pat) {
        StringBuilder answer = new StringBuilder();
        StringBuilder answer1 = new StringBuilder();
        for(int i = 0; i < myString.length(); i++){
            answer.append(myString.charAt(i));
        }
        } int count = answer.lastIndexOf(pat);
        answer1.append(answer.substring(0,count));
        for(int j = 0; j < pat.length(); j++){
            answer1.append(pat.charAt(j));
        }
} return answer1.toString();

Solution

StringBuilder answer = new StringBuilder(); and StringBuilder answer1 = new StringBuilder();: Create two StringBuilder objects answer and answer1. These objects help us manipulate strings efficiently.

for(int i = 0; i < myString.length(); i++): Iterate over the input string myString, adding each character to answer. This ensures that answer contains the contents of myString.

int count = answer.lastIndexOf(pat);: Find the last occurrence of the string pat in the answer string and store it in count.

answer1.append(answer.substring(0, count)): Add the substring from the answer string to the last occurrence of the pat string to answer1. This substring is the string before the pat.

for(int j = 0; j < pat.length(); j++): Add each character of the pat string to answer1.

return answer1.toString();: Convert the final assembled answer1 string to a string and return it.

This code finds the last occurrence of pat in the input string myString, replaces that part of the string with pat, and returns it.