As part of a mini-project I'm doing, I need a way to reverse the digits of an integer in PARI/GP (the project is mainly on palindromic numbers and digit sums).
What I'm trying to achieve in code form is fun(13453)
giving 35431
.
For example, I've tried doing the following:
Vecrev(digits(13453))
gives out [3,5,4,3,1]
but I don't know how to concatenate each consecutive element in this list.
I don't think there is a preset function for this, as rev
, reverse
, or digitrev
are not defined in PARI/GP.
Could someone show me how this can be done? Preferably, loops are undesirable as I want a simple function to put into, say, an if
statement or a for
loop.
Or: fromdigits(Vecrev(digits(13453)))