in contests/code-festival-2014-quala/code_festival_qualA_b.rs [6:21]
fn main() {
input! {
a: String,
B: u64
}
let A: String = a;
let len = A.len();
let mut index = (B as usize) % len;
if index == 0 {
index = len - 1;
} else {
index -= 1;
}
println!("{}", A.as_bytes()[index] as char);
}