Arithmetic using a for loop

[heiro1]

Hello Everyone,
One thing that I was not able to fully understand even though I read through the section on it a few times, is the for loop. I mean, I understand the premise of (statement, condition, update statement). However, I do not quite understand how a math problem is affected by this.

Can someone clarify with a simple example of how this works using multiplication and division? I would really appreciate it!

Oh, and lastly, why would you use a do.. while loop? What is it good for when compared to say, a sentinel loop? Thanks!

[divideby0]

the do while loop test condition is at the bottom and executes at least once. It's useful for user input prompts and waiting for specific values.

int i = 100;

do
{
   cout << i << "\n";
   i += 10;
   // enter loop at least once

} while(i <= 100);

I'm not sure what you mean by multiplication and division of the for loop. Do you mean the increment and decrement values?

int i;

for(i=1; i <= 100; i *= 10) // mul
   cout << i << "\n";

for(i = 100; i >= 1; i /= 10) // div
   cout << i << "\n";