How to use C language, input an input and output it in turn, such as input 1234 and output 432 1, please explain, thank you.
# include & ltstdio.h & gt
Invalid version ()
{ char c；
if((c=getchar())！ = ' \ n ')rev()；
putchar(c)；
}
int main()
{ rev()；
Returns 0;
}