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pub struct Rng(u32);
impl Rng {
pub fn new(seed: u32) -> Self {
let mut rng = Self(seed.max(1));
rng.next();
rng
}
pub fn next(&mut self) -> u32 {
self.0 ^= self.0 << 13;
self.0 ^= self.0 >> 17;
self.0 ^= self.0 << 5;
self.0
}
pub fn range(&mut self, n: u32) -> u32 {
self.next() % n
}
pub fn f32(&mut self) -> f32 {
self.next() as f32 / u32::MAX as f32
}
pub fn chance(&mut self, p: f32) -> bool {
self.f32() < p
}
}
impl Default for Rng {
fn default() -> Self {
Self::new(u32::from_be_bytes(*b"CLNK"))
}
}
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