temperature converter

challenges/challenges.json

@@ -195,5 +195,17 @@
     "tags": [],
     "created_at": "2024-06-02T00:00:00Z",
     "updated_at": "2024-06-02T00:00:00Z"
+  },
+  {
+    "id": 17,
+    "title": "Temperature Converter",
+    "slug": "temperature-converter",
+    "short_description": "Implement a temperature converter that handles various units and errors.",
+    "language": "RUST",
+    "difficulty": "MEDIUM",
+    "track": "CONTROL_FLOW",
+    "tags": ["conversion", "error handling", "conditionals"],
+    "created_at": "2024-06-03T00:00:00Z",
+    "updated_at": "2024-06-03T00:00:00Z"
   }
 ]

challenges/temperature-converter/Cargo.toml

@@ -0,0 +1,6 @@
+[package]
+name = "temperature-converter"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]

challenges/temperature-converter/description.md

@@ -0,0 +1,42 @@
+In many real-world applications, converting temperatures between different units is a common task. For example, meteorologists, scientists, and engineers often need to convert temperatures from Celsius to Fahrenheit or Kelvin. In this challenge, you'll implement a function that **converts temperatures between these units using logical operators and conditional statements**.
+
+## Your task
+
+Your task is to write a function `convert_temperature` that takes three parameters: a **float** representing the temperature value, a **string** representing the **unit** of the input temperature, and another **string** representing the desired unit for the output temperature. The function should return a `Result` type with either the converted temperature as a float or an error message if the input is invalid.
+
+## Requirements
+
+- The function should correctly convert temperatures between **Celsius**, **Fahrenheit**, and **Kelvin**.
+- If the input unit or the desired output unit is not one of **"C", "F", or "K"**, the function should return an error message: `"Invalid unit"`.
+- If the conversion is successful, the function should return the converted temperature as a **float** in the `Ok` variant of the `Result`.
+
+## Did you know?
+
+The Celsius and Fahrenheit scales are named after the scientists **Anders Celsius** and **Daniel Gabriel Fahrenheit**, respectively. The **Kelvin scale**, on the other hand, is named after **Lord Kelvin**, a British physicist. Unlike the **Celsius** and **Fahrenheit** scales, which are based on the freezing and boiling points of water, the **Kelvin** scale is an absolute temperature scale based on the concept of absolute zero, the lowest possible temperature where all molecular motion ceases.
+
+## Example
+
+```rust
+let result = convert_temperature(100.0, "C", "F");
+assert_eq!(result, Ok(212.0));
+
+let result = convert_temperature(32.0, "F", "C");
+assert_eq!(result, Ok(0.0));
+
+let result = convert_temperature(0.0, "C", "K");
+assert_eq!(result, Ok(273.15));
+
+let result = convert_temperature(300.0, "K", "C");
+assert_eq!(result, Ok(26.85));
+
+let result = convert_temperature(100.0, "C", "X");
+assert_eq!(result, Err("Invalid unit".to_string()));
+```
+
+## Hints
+
+- To convert Celsius to Fahrenheit: \(F = C \times \frac{9}{5} + 32\)
+- To convert Fahrenheit to Celsius: \(C = (F - 32) \times \frac{5}{9}\)
+- To convert Celsius to Kelvin: \(K = C + 273.15\)
+- To convert Kelvin to Celsius: \(C = K - 273.15\)
+- Remember to handle invalid units with proper error messages.

challenges/temperature-converter/src/lib.rs

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+mod tests;
+
+pub fn convert_temperature(value: f64, from_unit: &str, to_unit: &str) -> Result<f64, String> {
+    match (from_unit, to_unit) {
+        ("C", "F") => Ok(value * 9.0 / 5.0 + 32.0),
+        ("F", "C") => Ok((value - 32.0) * 5.0 / 9.0),
+        ("C", "K") => Ok(value + 273.15),
+        ("K", "C") => Ok(value - 273.15),
+        ("F", "K") => Ok((value - 32.0) * 5.0 / 9.0 + 273.15),
+        ("K", "F") => Ok((value - 273.15) * 9.0 / 5.0 + 32.0),
+        _ => Err("Invalid unit".to_string()),
+    }
+}

challenges/temperature-converter/src/starter.rs

@@ -0,0 +1,4 @@
+pub fn convert_temperature(value: f64, from_unit: &str, to_unit: &str) -> Result<f64, String> {
+    // TODO: Implement the function here
+    // Your code here...
+}

challenges/temperature-converter/src/tests.rs

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+#[cfg(test)]
+mod tests {
+    use crate::convert_temperature;
+
+    #[test]
+    fn test_convert_celsius_to_fahrenheit() {
+        assert_eq!(convert_temperature(100.0, "C", "F"), Ok(212.0));
+    }
+
+    #[test]
+    fn test_convert_fahrenheit_to_celsius() {
+        assert_eq!(convert_temperature(32.0, "F", "C"), Ok(0.0));
+    }
+
+    #[test]
+    fn test_convert_celsius_to_kelvin() {
+        assert_eq!(convert_temperature(0.0, "C", "K"), Ok(273.15));
+    }
+
+    #[test]
+    fn test_convert_kelvin_to_celsius() {
+        let result = convert_temperature(300.0, "K", "C").unwrap();
+        let rounded_result = (result * 100.0).round() / 100.0;
+        assert_eq!(rounded_result, 26.85);
+    }
+
+    #[test]
+    fn test_invalid_unit() {
+        assert_eq!(
+            convert_temperature(100.0, "C", "X"),
+            Err("Invalid unit".to_string())
+        );
+    }
+
+    #[test]
+    fn test_convert_fahrenheit_to_kelvin() {
+        assert_eq!(convert_temperature(32.0, "F", "K"), Ok(273.15));
+    }
+
+    #[test]
+    fn test_convert_kelvin_to_fahrenheit() {
+        assert_eq!(convert_temperature(273.15, "K", "F"), Ok(32.0));
+    }
+}