round a number to the nearest integer in rust

To round a number to the nearest integer in Rust, we can use the round function from the num crate. Here's an example:

main.rs
use num::Float;

fn main() {
    let x = 3.14159;
    let rounded = x.round();
    println!("{} rounded to the nearest integer is {}", x, rounded);
}
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In this example, we first import the Float trait from the num crate, which provides a variety of mathematical functions for floating-point numbers. We then define a floating-point number x and use the round method to round it to the nearest integer. Finally, we print out the original number and the rounded value using println!.

Note that round returns a f64 value, so if you need an integer, you'll need to convert it using the as keyword:

main.rs
let rounded_int = x.round() as i32;
println!("{} rounded to the nearest integer is {}", x, rounded_int);
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