How to get the digits of a number without converting it to a string/ char array?

Question

How do I get what the digits of a number are in C++ without converting it to strings or character arrays?

Answer 1

Get all the individual digits into something like an array - two variants:

int i2array_BigEndian(int n, char a[11])
{//storing the most significant digit first
    int digits=//obtain the number of digits with 3 or 4 comparisons
    n<100000?n<100?n<10?1:2:n<1000?3:n<10000?4:5:n<10000000?n<1000000?6:7:n<100000000?8:n<1000000000?9:10;
    a+=digits;//init end pointer
    do{*--a=n%10;}while(n/=10);//extract digits
    return digits;//return number of digits
}

int i2array_LittleEndian(int n, char a[11])
{//storing the least significant digit first
    char *p=&a[0];//init running pointer
    do{*p++=n%10;}while(n/=10);//extract digits
    return p-a;//return number of digits
}