feat(pre-algebra): add is_factor and is_multiple

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rzmk 2023-09-20 17:27:28 -04:00
parent a380407f21
commit 186f76d4f7
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3 changed files with 205 additions and 19 deletions

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@ -1,4 +1,4 @@
//! Implementations of mathematical and technical concepts in Rust.
/// Various pre-algebra implementations including multiples (planned), factor pairs, etc.
/// Various pre-algebra implementations including factor pairs, factors, multiples, and more.
pub mod pre_algebra;

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@ -1,14 +1,14 @@
use std::collections::HashSet;
/// Finds all factor pairs for a given positive integer.
/// Finds all factor pairs for a positive integer `n`.
///
/// # Challenge
///
/// Write a program that finds all the factor pairs for a given number `n`.
/// Write a program that finds all the factor pairs for a number `n`.
///
/// # Description
///
/// Generates a `HashSet` of factor pairs for a given positive integer `n`.
/// Generates a `HashSet` of factor pairs for a positive integer `n`.
///
/// This function calculates and returns a `HashSet` containing all unique factor pairs
/// of the input positive integer `n`. A factor pair is a pair of positive integers
@ -57,15 +57,15 @@ pub fn get_factor_pairs(n: u32) -> HashSet<(u32, u32)> {
factor_pairs
}
/// Finds all factors of a given positive integer.
/// Finds all factors of a positive integer `n`.
///
/// # Challenge
///
/// Write a program that finds all the factors of a given number. Assume that `n` is a positive integer greater than or equal to 1.
/// Write a program that finds all the factors of a number. Assume that `n` is a positive integer greater than or equal to 1.
///
/// # Description
///
/// Generates a `HashSet` of factors for a given positive integer `n`.
/// Generates a `HashSet` of factors for a positive integer `n`.
///
/// This function calculates and returns a `HashSet` containing all unique factors
/// of the input positive integer `n`. A factor of `n` is a positive integer `a` where
@ -100,7 +100,7 @@ pub fn get_factor_pairs(n: u32) -> HashSet<(u32, u32)> {
pub fn get_factors(n: u32) -> HashSet<u32> {
let mut factors: HashSet<u32> = HashSet::new();
for num in 1..n+1 {
for num in 1..n + 1 {
if n % num == 0 {
factors.insert(num);
}
@ -108,6 +108,81 @@ pub fn get_factors(n: u32) -> HashSet<u32> {
factors
}
/// Checks if a positive integer `x` is a factor of another positive integer `y`.
///
/// # Challenge
///
/// Write a program that determines whether one positive integer is a factor of another.
///
/// # Description
///
/// Checks if a positive integer `x` is a factor of another positive integer `y`.
///
/// A factor of `y` is a positive integer `x` where `y` is evenly divisible by `x` (i.e., `y % x == 0`).
///
/// # Arguments
///
/// * `x` - The positive integer to determine whether it is a factor of `y` or not.
/// * `y` - The positive integer for which the factor check of `x` is performed.
///
/// # Returns
///
/// `true` if `x` is a factor of `y`, `false` otherwise.
///
/// # Examples
///
/// ```rust
/// use ladderz::pre_algebra::unit1::is_factor;
///
/// fn main() {
/// assert!(is_factor(2, 16)); // 2 is a factor of 16
/// assert!(!is_factor(3, 16)); // 3 is not a factor of 16
/// }
/// ```
///
/// # Note
///
/// This function determines if `x` is a factor of `y` by checking if `y` is evenly divisible by `x`
/// (i.e., `y % x == 0`).
pub fn is_factor(x: u32, y: u32) -> bool {
y % x == 0
}
/// Checks if a positive integer `x` is a multiple of another positive integer `y`.
///
/// # Challenge
///
/// Write a program that determines whether one positive integer is a multiple of another.
///
/// # Description
///
/// Checks if a positive integer `x` is a multiple of another positive integer `y`.
///
/// A multiple of `y` is a positive integer `x` where `x` is evenly divisible by `y` (i.e., `x % y == 0`).
///
/// # Arguments
///
/// * `x` - The positive integer to determine whether it is a multiple of `y` or not.
/// * `y` - The positive integer for which the multiple check of `x` is performed.
///
/// # Returns
///
/// `true` if `x` is a multiple of `y`, `false` otherwise.
///
/// # Examples
///
/// ```rust
/// use ladderz::pre_algebra::unit1::is_multiple;
///
/// fn main() {
/// assert!(is_multiple(16, 2)); // 16 is a multiple of 2
/// assert!(!is_multiple(16, 3)); // 16 is not a multiple of 3
/// }
/// ```
pub fn is_multiple(x: u32, y: u32) -> bool {
x % y == 0
}
#[cfg(test)]
mod tests {
use super::*;
@ -133,4 +208,26 @@ mod tests {
let expected_2: HashSet<u32> = [1, 2, 4, 8, 16].into();
assert_eq!(result_2, expected_2);
}
#[test]
fn test_is_factor() {
let result: bool = true;
let expected: bool = is_factor(2, 10);
assert_eq!(result, expected);
let result_2: bool = false;
let expected_2: bool = is_factor(3, 10);
assert_eq!(result_2, expected_2);
}
#[test]
fn test_is_multiple() {
let result: bool = true;
let expected: bool = is_multiple(10, 2);
assert_eq!(result, expected);
let result_2: bool = false;
let expected_2: bool = is_multiple(11, 2);
assert_eq!(result_2, expected_2);
}
}

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@ -24,7 +24,7 @@
"\n",
"> [Link to lesson](https://www.khanacademy.org/math/pre-algebra/pre-algebra-factors-multiples/pre-algebra-factors-mult/v/understanding-factor-pairs).\n",
"\n",
"**Write a program that finds all the factor pairs for a given number $n$.**\n",
"**Write a program that finds all the factor pairs for a number $n$.**\n",
"\n",
"- Do not repeat any pairs (e.g., consider `(2, 8)` and `(8, 2)` as the same).\n",
"- Assume that $n$ is a positive integer greater than or equal to 1 ($n \\in \\mathbb{Z}^+$).\n",
@ -38,7 +38,7 @@
},
{
"cell_type": "code",
"execution_count": 25,
"execution_count": 1,
"metadata": {},
"outputs": [],
"source": [
@ -72,7 +72,9 @@
"\n",
"> [Link to lesson](https://www.khanacademy.org/math/pre-algebra/pre-algebra-factors-multiples/pre-algebra-factors-mult/v/finding-factors-of-a-number).\n",
"\n",
"**Write a program that finds all the factors of a given number $n$.** Assume that $n$ is a positive integer greater than or equal to 1 ($n \\in \\mathbb{Z}^+$).\n",
"**Write a program that finds all the factors of a number $n$.**\n",
"\n",
"- Assume that $n$ is a positive integer greater than or equal to 1 ($n \\in \\mathbb{Z}^+$).\n",
"\n",
"For example for $n = 16$, the output of `get_factors(16)` may be:\n",
"\n",
@ -83,7 +85,7 @@
},
{
"cell_type": "code",
"execution_count": 27,
"execution_count": 2,
"metadata": {},
"outputs": [],
"source": [
@ -101,6 +103,93 @@
"assert get_factors(16) == {1, 2, 4, 8, 16}\n",
"assert get_factors(120) == {1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 30, 40, 60, 120}"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"## Finding factors and multiples\n",
"\n",
"> [Link to lesson](https://www.khanacademy.org/math/pre-algebra/pre-algebra-factors-multiples/pre-algebra-factors-mult/v/finding-factors-and-multiples)."
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"**Write a program that checks if a number $x$ is a factor of $y$.**\n",
"\n",
"- Assume that $x$ and $y$ are positive integers greater than or equal to 1 ($x, y \\in \\mathbb{Z}^+$).\n",
"\n",
"For example, for $x = 2$ and $y = 10$, the output of `is_factor(2, 10)` may be:\n",
"\n",
"```\n",
"True\n",
"```"
]
},
{
"cell_type": "code",
"execution_count": 3,
"metadata": {},
"outputs": [],
"source": [
"def is_factor(x: int, y: int) -> bool:\n",
" return y % x == 0\n",
"\n",
"assert is_factor(2, 10) == True\n",
"assert is_factor(3, 10) == False"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"**Write a program that checks if a number $x$ is a multiple of $y$.**\n",
"\n",
"- Assume that $x$ and $y$ are positive integers greater than or equal to 1 ($x, y \\in \\mathbb{Z}^+$).\n",
"\n",
"For example, for $x = 20$ and $y = 3$, the output of `is_multiple(20, 3)` may be:\n",
"\n",
"```\n",
"True\n",
"```"
]
},
{
"cell_type": "code",
"execution_count": 4,
"metadata": {},
"outputs": [],
"source": [
"def is_multiple(x: int, y: int) -> bool:\n",
" return x % y == 0\n",
"\n",
"assert is_multiple(10, 2) == True\n",
"assert is_multiple(10, 3) == False"
]
},
{
"cell_type": "markdown",
"metadata": {},
"source": [
"**Write a program that finds all multiples of a given number $n$ up to a given limit $l$.**\n",
"\n",
"- Assume that $n$ and $l$ are positive integers greater than or equal to 1 ($n, l \\in \\mathbb{Z}^+$).\n",
"\n",
"For example for $n = 3$ and $l = 20$, the output of `get_multiples(3, 20)` may be:\n",
"\n",
"```\n",
"{3, 6, 9, 12, 15, 18}\n",
"```"
]
},
{
"cell_type": "code",
"execution_count": null,
"metadata": {},
"outputs": [],
"source": []
}
],
"metadata": {