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ex12.rs
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ex12.rs
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fn is_prime(num:u64) -> bool {
for i in 2..(num / 2 + 1) {
if num % i == 0 {
return false;
}
}
return true;
}
struct Prime {
curr: u64,
}
impl Iterator for Prime {
type Item = u64;
fn next(&mut self) -> Option<u64> {
let mut new_next = self.curr + 1;
while !is_prime(new_next) {
new_next += 1;
}
self.curr = new_next;
Some(self.curr)
}
}
// Returns the primes
fn primes() -> Prime {
Prime { curr: 1 }
}
fn main() {
let mut num = 0u64;
// Cache the primes we'll be using
let first_primes: Vec<u64> = primes().take(1000).collect();
for i in 1..1000000u64 {
num += i;
let mut num_div = 1u64;
let mut num_tmp = num;
for &x in &first_primes {
let prime = x;
if (num % prime) == 0 {
let mut exponent = 1;
while (num_tmp % prime) == 0 {
exponent += 1;
num_tmp /= prime;
}
num_div *= exponent;
}
if num_tmp == 1 { break; }
}
if num_div > 500 {
println!("num: {}", num);
return;
}
}
}