g2201_2300.s2243_calculate_digit_sum_of_a_string

Class Solution

java.lang.Object

g2201_2300.s2243_calculate_digit_sum_of_a_string.Solution

public class Solution
extends Object

2243 - Calculate Digit Sum of a String.

Easy

You are given a string s consisting of digits and an integer k.

A round can be completed if the length of s is greater than k. In one round, do the following:

1. Divide s into consecutive groups of size k such that the first k characters are in the first group, the next k characters are in the second group, and so on. Note that the size of the last group can be smaller than k.
2. Replace each group of s with a string representing the sum of all its digits. For example, "346" is replaced with "13" because 3 + 4 + 6 = 13.
3. Merge consecutive groups together to form a new string. If the length of the string is greater than k, repeat from step 1.

Return s after all rounds have been completed.

Example 1:

Input: s = “11111222223”, k = 3

Output: “135”

Explanation:

• For the first round, we divide s into groups of size 3: “111”, “112”, “222”, and “23”.

Then we calculate the digit sum of each group: 1 + 1 + 1 = 3, 1 + 1 + 2 = 4, 2 + 2 + 2 = 6, and 2 + 3 = 5.

So, s becomes “3” + “4” + “6” + “5” = “3465” after the first round.

• For the second round, we divide s into “346” and “5”.

Then we calculate the digit sum of each group: 3 + 4 + 6 = 13, 5 = 5.

So, s becomes “13” + “5” = “135” after second round.

Now, s.length <= k, so we return “135” as the answer.

Example 2:

Input: s = “00000000”, k = 3

Output: “000”

Explanation:

We divide s into “000”, “000”, and “00”.

Then we calculate the digit sum of each group: 0 + 0 + 0 = 0, 0 + 0 + 0 = 0, and 0 + 0 = 0.

s becomes “0” + “0” + “0” = “000”, whose length is equal to k, so we return “000”.

Constraints:

• 1 <= s.length <= 100
• 2 <= k <= 100
• s consists of digits only.

Constructor Summary

Constructors

Constructor and Description
Solution()

Method Summary

Modifier and Type	Method and Description
String	digitSum(String s, int k)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Solution

public Solution()

Method Detail

digitSum

public String digitSum(String s,
                       int k)