Take K Of Each Character From Left And Right - Leetcode Solution

Problem Description:

The problem "Take K of Each Character From Left and Right" is a LeetCode problem number 1418. The problem statement is as follows:

Given a string s and an integer k. You need to take k characters from the left index of s and another k characters from the right index of s and concatenate them to form a new string.

Return the new string.

If there are fewer than k characters in the string, then the result should be empty string "".

Input:

The input consists of two elements:

1. A string s, which consists of lowercase English letters.
2. An integer k, which denotes the number of characters to be taken from the left and right indices of the string s.

Output:

The output consists of a single string, which is the result of taking k characters from the left and right indices of the string s and concatenating them.

Solution:

The solution to this problem involves the following steps:

1. Check if the given string s contains fewer than k characters. If so, return an empty string.

2. Otherwise, take the first k characters from the left index of the string s and the last k characters from the right index of the string s.

3. Finally, concatenate the two strings obtained in step 2 and return the resulting string.

The implementation of the above solution using Python is given below:

class Solution:
    def getKthSubstring(self, s: str, k: int) -> str:
        if len(s) < k:
            return ""
        else:
            left_str = s[:k]
            right_str = s[-k:]
            return left_str + right_str

The above code defines a class Solution with a function getKthSubstring that takes a string s and an integer k as input and returns a string.

In the function getKthSubstring, the first if condition checks if the length of the string s is less than k. If it is less than k, an empty string is returned.

Otherwise, two new strings are obtained using slicing, left_str which is the first k characters from the left index of the string s, and right_str which is the last k characters from the right index of the string s.

Finally, the two strings are concatenated using the + operator and returned as the result.

Example:

Input: s = "abcdef" k = 2 Output: "abef"

Explanation: The first k characters from the left index of s are "ab" and the last k characters from the right index of s are "ef". Therefore, "abef" is the result.

Conclusion:

The problem "Take K of Each Character From Left and Right" is a simple problem that can be solved using string slicing and concatenation in Python.

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