Compilare: warning: unnecessary parentheses around `if` condition --> main.rs:17:12 | 17 | if (v.len() < 9) { | ^ ^ | = note: `#[warn(unused_parens)]` on by default help: remove these parentheses | 17 - if (v.len() < 9) { 17 + if v.len() < 9 { | warning: unused `Result` that must be used --> main.rs:20:13 | 20 | writeln!(fout, "{}", solution(&v)); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | = note: `#[warn(unused_must_use)]` on by default = note: this `Result` may be an `Err` variant, which should be handled = note: this warning originates in the macro `writeln` (in Nightly builds, run with -Z macro-backtrace for more info) warning: variable `nonNull` should have a snake case name --> main.rs:30:13 | 30 | let mut nonNull = 0; | ^^^^^^^ help: convert the identifier to snake case: `non_null` | = note: `#[warn(non_snake_case)]` on by default warning: 3 warnings emitted