Problem 3079. Big numbers, repeated least significant digits
Given an integer x which contains d digits, find the value of (minimum) n (n > 1) such that the last d digits of x^n is equal to x. If the last d digits will never equal x, return inf.
Example 1:
- x = 2; (therefore d = 1)
- 2^2 = 4, 2^3 = 8, 2^4 = 16, 2^5 = 32
- n = 5;
Example 2:
- x = 10; (therefore d = 2)
- 10^2 = 100, 10^3 = 1000, etc
- n = inf;
Solution Stats
Problem Comments
-
3 Comments
rifat
on 14 Mar 2015
is it correct for 35197? Im getting 5001 instead of inf.
Tim
on 15 Mar 2015
I also get 5001.
Rafael S.T. Vieira
on 3 Sep 2020
10016 and 10081 have another valid answer: 1251 (besides 626). The problem should accept them or request the minimum exponent.
Solution Comments
Show commentsProblem Recent Solvers71
Suggested Problems
-
Flip the main diagonal of a matrix
808 Solvers
-
541 Solvers
-
Cell Counting: How Many Draws?
1901 Solvers
-
234 Solvers
-
4238 Solvers
More from this Author4
Problem Tags
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!