Given a number N, the task is to reduce it to a single-digit number by repeatedly subtracting the adjacent digits. That is, in the first iteration, subtract all of the adjacent digits to generate a new number, if this number contains more than one digit, repeat the same process until it becomes a single-digit number.
Input: N = 6972
| 6 – 9 | = 3
| 9 – 7 | = 2
| 7 – 2 | = 5
After first step we get 325 but 325 is not a single-digit number so we’ll further reduce it until we do not get single digit number.
| 3 – 2 | = 1
| 2 – 5 | = 3
And now the number will become 13, we’ll reduce it furthur
| 1 – 3 | = 2
Input: N = 123456
Approach: Here we are using Array to represent the inital number N for simplicity.
- Count the number of digits in N and store the value in l.
- Create an array a of size l.
- Copy the given number into the array a.
- Calculate the RSF by subtracting the consecutive digits of array a.
Below is the implementation of the above approach:
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