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use crate::{Bit, Integer};
impl Integer {
pub fn pow(&self, e: &Integer) -> Result<Integer, Box<dyn std::error::Error>> {
if self == &Integer::zero() {
Ok(Integer::zero())
} else if e == &Integer::zero() {
Ok(Integer::one())
} else if e.0[0] == Bit::One {
Err("Non Integer result for negative exponent!")?
} else {
Ok(
e.0
.iter()
.skip(2)
.fold(
self.clone(),
|acc, x| {
let mut result = &acc * &acc;
if x == &Bit::One {
result *= self
}
result
}
)
)
}
}
}