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pub fn binary_search<F>(
is_ok: F,
max_epoch: usize,
mut ng: f64,
mut ok: f64,
) -> f64
where
F: Fn(f64) -> bool,
{
for _ in 0..max_epoch {
let x = (ng + ok) / 2.;
if is_ok(x) {
ok = x;
} else {
ng = x;
}
}
ok
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test() {
assert_eq!(
binary_search(|x| x * x >= 1000., 20, 0., 100.),
31.622791290283203,
);
assert_eq!(
binary_search(|x| x * x <= 1000., 20, 100., 0.),
31.622695922851563,
);
}
}