bigint
Fixed-sized integers arithmetic
extern crate bigint;
use bigint::U256;
fn main() {
let mut val: U256 = 1023.into();
for _ in 0..200 { val = val * 2.into() }
assert_eq!(
&format!("{}", val),
"1643897619276947051879427220465009342380213662639797070513307648"
);
}