Class Solution

java.lang.Object
g2701_2800.s2719_count_of_integers.Solution

public class Solution extends Object
2719 - Count of Integers.

Hard

You are given two numeric strings num1 and num2 and two integers max_sum and min_sum. We denote an integer x to be good if:

  • num1 <= x <= num2
  • min_sum <= digit_sum(x) <= max_sum.

Return the number of good integers. Since the answer may be large, return it modulo 109 + 7.

Note that digit_sum(x) denotes the sum of the digits of x.

Example 1:

Input: num1 = “1”, num2 = “12”, min_sum = 1, max_sum = 8

Output: 11

Explanation: There are 11 integers whose sum of digits lies between 1 and 8 are 1,2,3,4,5,6,7,8,10,11, and 12. Thus, we return 11.

Example 2:

Input: num1 = “1”, num2 = “5”, min_sum = 1, max_sum = 5

Output: 5

Explanation: The 5 integers whose sum of digits lies between 1 and 5 are 1,2,3,4, and 5. Thus, we return 5.

Constraints:

  • 1 <= num1 <= num2 <= 1022
  • 1 <= min_sum <= max_sum <= 400
  • Constructor Details

    • Solution

      public Solution()
  • Method Details

    • count

      public int count(String num1, String num2, int minSum, int maxSum)