various clarifications and reformating

subjects/fibonacci2/README.md

@@ -11,12 +11,10 @@ Each number in the series is calculated by the summing of the two previous ones
 - so fibonacci(2) = 1 (1 + 1) 
 - and fibonnacci(4) = 3 (1 + 2)
 
-### TNotions
+### Notions
 
-#### Primitives
-- https://doc.rust-lang.org/stable/rust-by-example/primitives.html
-#### Functions
-- https://doc.rust-lang.org/stable/rust-by-example/fn.html
+- [Primitives](https://doc.rust-lang.org/stable/rust-by-example/primitives.html)
+- [Functions](https://doc.rust-lang.org/stable/rust-by-example/fn.html)
 
 ### Expected function
 

subjects/find_factorial/README.md

@@ -2,7 +2,13 @@
 
 ### Instruccions
 
-Complete the function `factorial` to return the factorial of a given number
+Complete the **function** `factorial` to return the factorial of a given number.
+
+As a reminder the factorial of a number is the product of all the integers from 1 to that number.
+
+Example: the factorial of 6 (written 6!) is 1*2*3*4*5*6 = 720.
+
+Do not forget the rules for 0 and 1.
 
 ### Expected Function
 

subjects/groceries/README.md

@@ -2,13 +2,14 @@
 
 ### Instructions
 
-Create a function called `insert` that inserts a new element at the end of the Vec
+Create a **function** called `insert` that inserts a new element at the end of the `Vec`.
 
-And another function `at_index` that returns the value found at the index passed as an argument
+And another **function** `at_index` that returns the value found at the index passed as an argument.
 
 ### Notions
 
-[Common Collections]( https://doc.rust-lang.org/stable/book/ch08-00-common-collections.html)
+- [Common Collections](https://doc.rust-lang.org/stable/book/ch08-00-common-collections.html)
+- [Vectors]https://doc.rust-lang.org/stable/book/ch08-01-vectors.html)
 
 ### Expected Functions
 
@@ -16,7 +17,7 @@ And another function `at_index` that returns the value found at the index passed
 pub fn insert(vec: &mut Vec<String>, val: String) {
 }
 
-pub fn at_index(vec: &Vec<String>, index: ) -> String {
+pub fn at_index(vec: &Vec<String>, index: usize) -> String {
 }
 ```
 
@@ -25,7 +26,7 @@ pub fn at_index(vec: &Vec<String>, index: ) -> String {
 Here is a possible program to test your function:
 
 ```rust
-use groceries::{insert, at_index}
+use groceries::{insert, at_index};
 
 fn main() {
 	let mut groceries = vec![

subjects/looping/README.md

@@ -2,11 +2,11 @@
 
 ### Instructions
 
-Write a program that prints a riddle, receives input from the user and checks that the answer is correct
+Write a **program** that prints a riddle, receives input from the user and checks that the answer is correct.
 
-The program must allow indefinite number of trials and only quit after the correct answer is given
+The program must allow indefinite number of trials and only quit after the correct answer is given.
 
-Every time the user introduces an incorrect answer the program must print the riddle again and after the user gives the correct answer the program must print the number of tries that took to get the correct answer
+Every time the user introduces an incorrect answer the program must print the riddle again and after the user gives the correct answer the program must print the number of tries that took to get the correct answer.
 
 Riddle: I am the beginning of the end, and the end of time and space. I am essential to creation, and I surround every place. What am I?
 

subjects/matrix_transposition/README.md

@@ -2,9 +2,9 @@
 
 ### Instructions
 
-- Define the structure matrix as a tuple of tuples of `i32`'s
+- Define the structure matrix as a tuple of 2 tuples of 2 `i32`'s.
 
-- Define a function that calculate the transpose matrix of a 2x2 matrix.
+- Define a function that calculates the transpose matrix of a 2x2 matrix.
 
 - Note:
 
@@ -17,13 +17,21 @@ Example:
 ( c d )                          ( b d )
 ```
 
-- Matrix must implement Debug, PartialEq and Eq. You can use derive
+- Matrix must implement Debug, PartialEq and Eq. You can use derive.
 
-- Remember that you're defining a library so you have to make public the elements that are going to be called from an external crate.
+- Remember that you are defining a library so you have to make public the elements that are going to be called from an external crate.
 
 ### Notions
 
-[Chapter 7]( https://doc.rust-lang.org/stable/book/ch07-03-paths-for-referring-to-an-item-in-the-module-tree.html )
+- [Defining a struct](https://doc.rust-lang.org/stable/book/ch05-01-defining-structs.html)
+
+- [The Tuple Type](https://doc.rust-lang.org/stable/book/ch03-02-data-types.html?highlight=accessing%20a%20tuple#compound-types)
+
+- [Tuple Structs without Named Fields](https://doc.rust-lang.org/stable/book/ch05-01-defining-structs.html?highlight=tuple#using-tuple-structs-without-named-fields-to-create-different-types)
+
+- [Adding Useful Functionality with Derived Traits](https://doc.rust-lang.org/stable/book/ch05-02-example-structs.html?highlight=debug%20deriv#adding-useful-functionality-with-derived-traits)
+
+- [Chapter 7](https://doc.rust-lang.org/stable/book/ch07-03-paths-for-referring-to-an-item-in-the-module-tree.html)
 
 ### Expected Function
 
@@ -37,6 +45,8 @@ pub fn transpose(m: Matrix) -> Matrix {
 Here is a posible program to test your function
 
 ```rust
+use matrix_transposition::transpose;
+
 fn main() {
     let matrix = Matrix((1, 3), (4, 5));
     println!("Original matrix {:?}", matrix);
@@ -44,7 +54,7 @@ fn main() {
 }
 ```
 
-And it's output:
+And its output:
 
 ```console
 student@ubuntu:~/[[ROOT]]/test$ cargo run

subjects/reverse_string/README.md

@@ -2,7 +2,14 @@
 
 ### Instructions
 
-Write a function `rev_str` that takes a `&str` as a parameter, and returns a string with its words reversed.
+Write a **function** `rev_str` that takes a `&str` as a parameter, and returns a `String` with its letters reversed.
+
+### Notions
+
+- [Strings](https://doc.rust-lang.org/rust-by-example/std/str.html)
+- [Primitive Type str](https://doc.rust-lang.org/std/primitive.str.html)
+- [Primtive Type char](https://doc.rust-lang.org/std/primitive.char.html)
+- [Module std::string](https://doc.rust-lang.org/std/string/index.html)
 
 ### Expected Functions
 
@@ -27,7 +34,7 @@ fn main() {
 }
 ```
 
-And it's output:
+And its output:
 
 ```console
 student@ubuntu:~/[[ROOT]]/test$ cargo run

subjects/scalar/README.md

@@ -11,7 +11,7 @@ Create the following **functions**, which each receives two parameters:
 You **must** complete the Expected functions parameters data type accordingly (Replace the Xs)! 
 
 ### Notions
-- https://doc.rust-lang.org/book/ch03-02-data-types.html
+- [Data Types](https://doc.rust-lang.org/book/ch03-02-data-types.html)
 
 
 ### Expected functions (Incomplete, you must precise the Data Types)
@@ -38,30 +38,27 @@ pub fn rem(a: X, b: X) -> X {
 }
 ```
 
-### Usage (do not forget to comment the ERROR test if you want to use all the tests):
+### Usage :
+#### Note that There is no output for this test for you to train to comment accordingly.
 
 ```rust
-use scalar::sum;
-use scalar::diff;
-use scalar::pro;
-use scalar::quo;
-use scalar::rem;
+use scalar::*;
 
 fn main() {
     // sum
-    println!("sum : {}", sum(234, 2));
+    println!("sum : {}", sum(234, 2)); // 'sum : 236'
     println!("sum : {}", sum(1, 255)); // 'ERROR: attempt to add with overflow'
     // diff
-    println!("diff : {}", diff(234, 2));
+    println!("diff : {}", diff(234, 2)); // 'diff : 232'
     println!("diff : {}", diff(-32768, 32766)); // 'ERROR: attempt to subtract with overflow'
     // product
-    println!("pro : {}", pro(23, 2));
+    println!("pro : {}", pro(23, 2)); // 'pro : 46'
     println!("pro : {}", pro(-128, 2)); // 'ERROR: attempt to multiply with overflow'
     // quotient
-    println!("quo : {}", quo(22.0, 2.0));
-    println!("quo : {}", quo(-128.23, 2.0));
+    println!("quo : {}", quo(22.0, 2.0));// 'quo : 11'    
+    println!("quo : {}", quo(-128.23, 2.0));// 'quo : -64.115'
     // remainder
-    println!("rem : {}", rem(22.0, 2.0));
-    println!("rem : {}", rem(-128.23, 2.0));
+    println!("rem : {}", rem(22.0, 2.0));// 'rem : 0'
+    println!("rem : {}", rem(-128.23, 2.0));// 'rem : -0.22999573'
 }
 ```

subjects/speed_transformation/README.md

@@ -2,19 +2,20 @@
 
 ### Instructions
 
-Create a function that receives the speed in km/h (kilometers per hour) and returns the equivalent in m/s (meters per second)
+Create a **function** that receives the speed in km/h (kilometers per hour) and returns the equivalent in m/s (meters per second).
 
 ### Expected Function
 
 ```rust
 pub fn km_per_hour_to_meters_per_second(km_h: f64) -> f64 {
-	(10.0 / 36.0) * km_h
 }
 ```
 
 ### Usage
 
 ```rust
+use speed_transformation::km_per_hour_to_meters_per_second;
+
 fn main() {
 	let km_h = 100.0;
 	let m_s = km_per_hour_to_meters_per_second(km_h);

subjects/temperature_conv/README.md

@@ -2,15 +2,17 @@
 
 ### Instructions
 
-Write two functions to transform values of temperatures from celcius to fahrenheit and the other way arraound:
+Write two functions which convert values of temperatures from `fahrenheit` to `celcius` and the other way around.
 
-### Expected funcions
+To pass this exercise you must use (9/5) in **both** functions.
+
+### Expected functions
 
 ```rust
-fn fahrenheit_to_celsius(f: f64) -> f64 {
+pub fn fahrenheit_to_celsius(f: f64) -> f64 {
 }
 
-fn celsius_to_fahrenheit(c: f64) -> f64 {
+pub fn celsius_to_fahrenheit(c: f64) -> f64 {
 }
 ```
 
@@ -19,9 +21,18 @@ fn celsius_to_fahrenheit(c: f64) -> f64 {
 ```rust
 use temperature_conv::*;
 
-
 fn main() {
 	println!("{} F = {} C", -459.67, fahrenheit_to_celsius(-459.67));
 	println!("{} C = {} F", 0.0, celsius_to_fahrenheit(0.0));
 }
 ```
+
+And its output:
+
+```console
+student@ubuntu:~/[[ROOT]]/test$ cargo run
+-459.67 F = -273.15 C
+0 C = 32 F
+student@ubuntu:~/[[ROOT]]/test$
+```
+