Compilare: warning: variable does not need to be mutable --> main.rs:6:17 | 6 | fn makes_square(mut x : &(i32, i32), mut y : &(i32, i32), set : &BTreeSet<(i32, i32)>) -> bool { | ----^ | | | help: remove this `mut` | = note: `#[warn(unused_mut)]` on by default warning: variable does not need to be mutable --> main.rs:6:38 | 6 | fn makes_square(mut x : &(i32, i32), mut y : &(i32, i32), set : &BTreeSet<(i32, i32)>) -> bool { | ----^ | | | help: remove this `mut` warning: unused `std::result::Result` that must be used --> main.rs:55:5 | 55 | writeln!(output, "{}", counter / 4); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | = 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 a macro (in Nightly builds, run with -Z macro-backtrace for more info) warning: 3 warnings emitted