Special Sum of Array Problem Statement

Given an array 'arr' containing single-digit integers, your task is to calculate the total sum of all its elements. However, the resulting sum must also be a single-digit number. To achieve this, repeatedly sum the digits of the result until a single-digit number is obtained.

Example:

Input:

[5, 8, 4, 9]

Output:

8

Explanation:

The sum of the elements is 26. The sum of the digits 2 + 6 = 8 is a single-digit number.

Constraints:

1

Question

Special Sum of Array Problem Statement

Given an array 'arr' containing single-digit integers, your task is to calculate the total sum of all its elements. However, the resulting sum must also be a single-digit number. To achieve this, repeatedly sum the digits of the result until a single-digit number is obtained.

Example:

Input:

[5, 8, 4, 9]

Output:

Explanation:

The sum of the elements is 26. The sum of the digits 2 + 6 = 8 is a single-digit number.

Constraints:

1 <= T <= 100
1 <= N <= 10^3
0 <= arr[i] <= 9
The sum of 'N' across all test cases does not exceed 10^5.

Time Limit: 1 sec.

Accepted Answer

Calculate the total sum of array elements until a single-digit number is obtained by repeatedly summing digits.

Iterate through the array and calculate the sum of all elements.
If the sum is a single-digit number, return it. Otherwise, repeat the process of summing digits until a single-digit number is obtained.
Return the final single-digit sum.

Accepted Answer

def num(n):
    if n &lt; = 9 :
        return n
    while len(str(n)) > 1:
        string=str(n)
        sum=0
        for i in range(len(string)):
            sum=sum+int(string[i])
        if len(str(sum))==1:
            return sum
        else:
            return num(sum)