Functions and return values

Functions are declared with fn. Every parameter needs a type, and so does the return value, written after ->.

In Rust, the last expression in a function body is its return value. Note the missing semicolon: adding ; turns an expression into a statement that returns () instead.

fn double(x: i32) -> i32 {
    x * 2
}

Your task

Write a public function celsius_to_fahrenheit that takes an f64 and returns the temperature in Fahrenheit as an f64. The formula is c * 9.0 / 5.0 + 32.0.