Compilare: warning: unused variable: `i` --> main.rs:13:6 | 13 | for i in 0..(n+1) { | ^ help: consider using `_i` instead | = note: #[warn(unused_variables)] on by default warning: unused `std::result::Result` which must be used --> main.rs:30:3 | 30 | fs::write("minmax.out", format!("{}\n", ans[i as usize]) ); | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | = note: #[warn(unused_must_use)] on by default = note: this `Result` may be an `Err` variant, which should be handled