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Rust program to demonstrate the de-referencing of the dynamically allocated variable

Rust Example: Write a program to demonstrate the de-referencing of the dynamically allocated variable.
Last Updated : November 25, 2021

Problem Statement

In this program, we will create a variable that will allocate space into the HEAP area of memory using the Box::new() function, and then we will use the "*" dereferencing operator to access the value of the created variable.

Program/Source Code

The source code to demonstrate the de-referencing of dynamically allocated variables is given below. The given program is compiled and executed on UBUNTU 18.04 successfully.

// Rust program to demonstrate the de-referencing 
// of dynamically allocated variable

fn main() {
    let number = Box::new(5); 
    
    // if number == 5 
    // Above statement - generate error that's
    // why dereferencing is required
    
    if *number == 5
    {
        println!("Hello");
    }
    else
    {
        println!("Hiiii");
    }
}

Output

Hello

Explanation

In the main() function, we used Box::new() function to create a variable in the HEAP area of memory. Then we used the "*" dereferencing operator to access the value of the created variable and printed the appropriate message based on the if condition.

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