How do I remove the first number from an integer?

Question

I need to intake a number like: 200939915

After doing this, which I know how, I need to remove the first number so it becomes: 00939915

What is the best way

Answer 1

An alternative method, although I like Matt Kane's best:

unsigned long n = 42424242;
n = n % (unsigned long)pow(10.0, (double)floor(log10(n)));
// n = 2424242;