Find K'th Character of Decrypted String

You are given an encrypted string where repeated substrings are represented by the substring followed by its count. Your task is to find the K'th character of the decrypted string. The decrypted string is 1-based indexed.

For example, the string "aabbbcdcdcd" can be encrypted as "a2b3cd3".

Input:

The first line contains an encrypted string 'S'.
The second line contains an integer 'K'.

Output:

Output the K'th character of the decrypted string derived from the encrypted string 'S'.

Example:

Input:

S = "a2b3cd1e2"
K = 5

Output:

c

Constraints:

2

Question

Find K'th Character of Decrypted String

You are given an encrypted string where repeated substrings are represented by the substring followed by its count. Your task is to find the K'th character of the decrypted string. The decrypted string is 1-based indexed.

For example, the string "aabbbcdcdcd" can be encrypted as "a2b3cd3".

Input:

The first line contains an encrypted string 'S'.
The second line contains an integer 'K'.

Output:

Output the K'th character of the decrypted string derived from the encrypted string 'S'.

Example:

Input:

S = "a2b3cd1e2"
K = 5

Output:

Constraints:

2 <= N <= 10⁵
1 <= K <= M
1 <= M <= 10¹⁸

Note:

Input string consists of lowercase characters only, without spaces.
If a substring count is 1, it will be followed by the integer '1' (e.g., "aabcdee" -> "a2bcd1e2").
The frequency can be more than one digit (e.g., "ab12c3").
The frequency can be in parts (e.g., "aaaabbbb" can be "a2a2b3b1").
You are not required to print the result; just implement the function logic.

Accepted Answer

Given an encrypted string with repeated substrings represented by counts, find the K'th character of the decrypted string.

Parse the encrypted string to extract substrings and their counts
Iterate through the substrings and counts to build the decrypted string
Track the position in the decrypted string to find the K'th character

Accepted Answer

function findKthElement(encryptedStr , k){
    let decryptedStr = ''
    
    let i = 0
    

    //Decrypting the String
    while(i < encryptedStr.length){
        let currentChar = ''
        let count= ''
        while(i < encryptedStr.length && isNaN(encryptedStr[i])){
            currentChar += encryptedStr[i]
            i++
        }

        count = ''
        while(i < encryptedStr.length && !isNaN(encryptedStr[i])){
            count += encryptedStr[i]
            i++
        }

        let repateation = parseInt(count) || 1 //if the count is NAN then it will make it 1 
        for(let j=0 ; j < repateation; j++){
            decryptedStr += currentChar
        }
    }

    //find kth value
    return decryptedStr.charAt(k - 1)
}

Find K'th Character of Decrypted String

Input:

Output:

Example:

Input:

Output:

Constraints:

Note:

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