thread-spawn
2024-03-06
exampleslangsrustuse std::thread;
fn is_prime(n: i32) -> bool {
let mut result = true;
for k in 2..(n as f32).powf(0.5) as i32 + 1 {
if n % k == 0 {
result = false;
break;
}
}
result
}
fn count_primes(start: i32, end: i32) -> i32 {
let mut count = 0;
for k in start..end {
if is_prime(k) {
count += 1;
}
}
count
}
fn main() {
const THREAD_COUNT: usize = 15; // 设置线程数量
let n = 1e8 as i32;
let chunk_size = n / THREAD_COUNT as i32;
let mut handles = vec![];
for i in 0..THREAD_COUNT {
let start = i as i32 * chunk_size + 2;
let end = if i == THREAD_COUNT - 1 {
n
} else {
(i + 1) as i32 * chunk_size + 2
};
let handle = thread::spawn(move || count_primes(start, end));
handles.push(handle);
}
let mut total_count = 0;
for handle in handles {
total_count += handle.join().unwrap();
}
println!("{}", total_count);