Rust program to calculate the perimeter of the circle

Program/Source Code:

The source code to calculate the perimeter of the circle is given below. The given program is compiled and executed successfully.

// Rust program to calculate the 
// perimeter of circle

use std::io;

fn main() {
    let mut radius:f32 = 0.0;
    let mut perimeter:f32 = 0.0;
    let mut input = String::new();
    
    println!("Enter radius: ");
    io::stdin().read_line(&mut input).expect("Not a valid string");
    radius = input.trim().parse().expect("Not a valid number");

    perimeter = 2.0 * 3.14 * radius;
 
    println!("Perimeter of circle: {}",perimeter);
}

Output:

RUN 1:
Enter radius: 
1.2
Perimeter of circle: 7.5360007

RUN 2:
Enter radius: 
5.15
Perimeter of circle: 32.342003

RUN 3:
Enter radius: 
10
Perimeter of circle: 62.800003

Explanation:

Here, we read the value of radius from the user and calculated the perimeter of the circle. After that, we printed the result.