咨询：C++判断质数的isprime()函数某步骤工作原理

Hey there! I totally get how frustrating it can be to hit a roadblock in a prime-checking function, even after putting in the work to research it. Those subtle optimizations or logical checks can feel opaque at first glance.

To break down that confusing step in your isprime() function for you, could you share the full code snippet you're working with? Make sure to point out exactly which line or section you're stuck on—whether it's an optimization like checking up to the square root, skipping even numbers after 2, or something else entirely. Once I can see the specific logic you're referring to, I can walk you through why it's necessary, how it works, and how it helps the function correctly identify primes.

Looking forward to helping you wrap your head around this!

内容的提问来源于stack exchange，提问作者Kanishk Tanwar