3756. Concatenate Non-Zero Digits and Multiply by Sum II

You are given a string s of length m consisting of digits. You are also given a 2D integer array queries, where queries[i] = [li, ri].

For each queries[i], extract the substring s[li..ri]. Then, perform the following:

Form a new integer x by concatenating all the non-zero digits from the substring in their original order. If there are no non-zero digits, x = 0.

Let sum be the sum of digits in x. The answer is x * sum.

Return an array of integers answer where answer[i] is the answer to the ith query.

Since the answers may be very large, return them modulo 109 + 7.

Example 1:

Input: s = "10203004", queries = [[0,7],[1,3],[4,6]]

Output: [12340, 4, 9]

Explanation:

s[0..7] = "10203004"

x = 1234

sum = 1 + 2 + 3 + 4 = 10

Therefore, answer is 1234 * 10 = 12340.

s[1..3] = "020"

x = 2

sum = 2

Therefore, the answer is 2 * 2 = 4.

s[4..6] = "300"

x = 3

sum = 3

Therefore, the answer is 3 * 3 = 9.

Example 2:

Input: s = "1000", queries = [[0,3],[1,1]]

Output: [1, 0]

Explanation:

s[0..3] = "1000"

x = 1

sum = 1

Therefore, the answer is 1 * 1 = 1.

s[1..1] = "0"

x = 0

sum = 0

Therefore, the answer is 0 * 0 = 0.

Example 3:

Input: s = "9876543210", queries = [[0,9]]

Output: [444444137]

Explanation:

s[0..9] = "9876543210"

x = 987654321

sum = 9 + 8 + 7 + 6 + 5 + 4 + 3 + 2 + 1 = 45

Therefore, the answer is 987654321 * 45 = 44444444445.

We return 44444444445 modulo (109 + 7) = 444444137.

Constraints:

1 <= m == s.length <= 105

s consists of digits only.

1 <= queries.length <= 105

queries[i] = [li, ri]

0 <= li <= ri < m

 Solution:

class Solution {

    public int[] sumAndMultiply(String s, int[][] queries) {

        int[] answers = new int[queries.length];

        for (int i = 0; i < queries.length; i++){

            long x = 0;

            long sum = 0;

            String sub = s.substring(queries[i][0], queries[i][1]+1);

            for (int j = 0; j < sub.length(); j++) {

                int numericValue = Character.getNumericValue(sub.charAt(j));

                if (numericValue != 0) {

                    x = x * 10 + numericValue;

                    sum += numericValue;

                }

            }

            answers[i] = (int) ((x * sum) % (Math.pow(10, 9) + 7));

        }

        return answers;

    }

}