Problem 1825. Find all vampire fangs
A vampire number is a number v that is the product of two numbers x and y such that the following conditions are satisfied:
- at most one of x and y are divisible by 10;
- x and y have the same number of digits; and
- The digits in v consist of the digits of x and y (including anyrepetitions).
If these conditions are met, x and y are known as "fangs" of v. For example, 1260 is a vampire number because 1260 = 21*60, so 21 and 60 are the fangs.
Write a function that returns all the pairs of fangs for a given number. The output is a matrix in which each row is a pair; the values in the first row should be in increasing order. If it is not a vampire number, it will return empty arrays.
Example:
disp(vampire_factor(125460))
204 615
246 510
Solution Stats
Problem Comments
-
2 Comments
DH
on 7 Dec 2024
Test 5 seems to be incorrect.
125460 and 125500 are vampire numbers.
125460 = 204*615 = 246*510.
125500 = 251*500.
Dyuman Joshi
on 8 Dec 2024
You are right, @DH.
Numbers generated through randi([imin imax]) syntax includes both the end values.
I have corrected the test case.
Solution Comments
Show commentsGroup

Sequences & Series I
- 14 Problems
- 87 Finishers
- Sum all integers from 1 to 2^n
- Integer sequence - 2 : Kolakoski sequence
- Sum all integers from 1 to 2^n
- Project Euler: Problem 2, Sum of even Fibonacci
- Sum of first n terms of a harmonic progression
- Project Euler: Problem 6, Natural numbers, squares and sums.
- Integer Sequence - II : New Fibonacci
- Project Euler: Problem 2, Sum of even Fibonacci
- Project Euler: Problem 6, Natural numbers, squares and sums.
- Find the stride of the longest skip sequence
- Sum the Infinite Series
- Return the Fibonacci Sequence
- Sum of first n terms of a harmonic progression
- "Look and say" sequence
- Is X a Fibonacci Matrix?
- Square Digits Number Chain Terminal Value (Inspired by Project Euler Problem 92)
- Golomb's self-describing sequence (based on Euler 341)
- Alternating sum
- Integer sequence - 2 : Kolakoski sequence
- Integer Sequence - II : New Fibonacci
Problem Recent Solvers70
Problem Tags
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!