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:
- Finding sum of digits of a number until sum becomes single digit
- Maximum of sum and product of digits until number is reduced to a single digit
- Sum of Digits in a^n till a single digit
- Reduce the array to a single integer with the given operation
- Number of times a number can be replaced by the sum of its digits until it only contains one digit
- Integers from the range that are composed of a single distinct digit
- Squares of numbers with repeated single digits | Set 1 (3, 6 and 9)
- Longest subarray such that adjacent elements have at least one common digit | Set - 2
- Longest subarray such that adjacent elements have at least one common digit | Set 1
- Longest subsequence such that adjacent elements have at least one common digit
- Count of Numbers in Range where first digit is equal to last digit of the number
- Find the remainder when First digit of a number is divided by its Last digit
- Print all n-digit numbers whose sum of digits equals to given sum
- Divisibility by 3 where each digit is the sum of all prefix digits modulo 10
- N digit numbers divisible by 5 formed from the M digits
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