Compilare: warning: unused variable: `f` --> main.rs:9:13 | 9 | let mut f = std::fs::File::open("aparitii.in").unwrap(); | ^ help: if this is intentional, prefix it with an underscore: `_f` | = note: `#[warn(unused_variables)]` on by default warning: unused variable: `n` --> main.rs:12:9 | 12 | let n = it.next().unwrap().parse::<usize>().unwrap(); | ^ help: if this is intentional, prefix it with an underscore: `_n` warning: variable does not need to be mutable --> main.rs:9:9 | 9 | let mut f = std::fs::File::open("aparitii.in").unwrap(); | ----^ | | | help: remove this `mut` | = note: `#[warn(unused_mut)]` on by default warning: 3 warnings emitted