Package g2201_2300.s2243_calculate_digit_sum_of_a_string

Class 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 Detail

      • Solution

        public Solution()

    • Method Detail