public/subjects/arrays

arrays

Instructions

Define a function named thirtytwo_tens that returns an array with 32 positions filled with only the value 10, so that [10, 10, 10, ... 10].len() is equal to 32.

Write a function that takes an array of i32 and returns the sum of the elements (make it work with the main).

Expected functions

The type of one of the arguments is missing. Use the example main function to determine the correct type.

pub fn sum(a: _) -> i32 {
	//type of argument missing in the signature here
}

pub fn thirtytwo_tens() -> [i32; 32] {
}

Usage

Here is a program to test your function.

It's incomplete. Use the output and the other available information to figure out what is missing.

use arrays::{sum, thirtytwo_tens};

fn main() {
	let a = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
	let a1: Vec<i32> = (1..11).; //missing info here
	let b = [_; 10]; //missing info here

	println!("The Sum of the elements in {:?} = {}", a, sum(a));//missing info here
	println!("The Sum of the elements in {:?} = ", a1, sum(a1));//missing info here
	println!("The Sum of the elements in {:?} = {}", b, sum(b));//missing info here
	println!(
		"Array size {} with only 10's in it {:?}",
		thirtytwo_tens().len(),
		thirtytwo_tens()
	);
}

And its output:

$ cargo run
The Sum of the elements in [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] = 55
The Sum of the elements in [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] = 55
The Sum of the elements in [5, 5, 5, 5, 5, 5, 5, 5, 5, 5] = 50
Array size 32 with only 10's in it [10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10]
$

Notions

• arrays