Rust Tutorials

How to print Hollow Inverted Pyramid Pattern in Rust

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How to print Hollow Inverted Pyramid Pattern in Rust ?

Answer

To print a hollow inverted pyramid pattern in Rust, we use nested loops to manage spaces and stars.

✐ Examples

1 Print Hollow Inverted Pyramid Pattern in Rust

In this example,

We assume the number of rows for the inverted pyramid is 5.
We then use nested loops where the outer loop controls the rows and the inner loop manages spaces and stars.
Within the loops, we use conditions to print stars only at specific positions to create the hollow effect.
The outer loop decrements from 5 to 1, managing the rows of the inverted pyramid.
The inner loop calculates the spaces required to position the stars correctly, ensuring the hollow pattern.
Stars are printed based on conditions to achieve the desired hollow inverted pyramid pattern.

Rust Program

fn main() {
    let num_rows = 5;

    for row in (1..=num_rows).rev() {
        let mut pattern = String::new();
        for _ in 0..(num_rows - row) {
            pattern.push(' ');
        }
        if row == num_rows || row == 1 {
            pattern.push_str(&"*".repeat(2 * row - 1));
        } else {
            pattern.push('*');
            pattern.push_str(&" ".repeat(2 * row - 3));
            pattern.push('*');
        }
        println!("{}", pattern);
    }
}

Output

*********
 *     *
  *   *
   * *
    *

Summary

In this tutorial, we learned How to print Hollow Inverted Pyramid Pattern in Rust language with well detailed examples.