diff --git a/exercises/basic-of-rust/src/conditions.rs b/exercises/basic-of-rust/src/conditions.rs
index 4d92e3b3..0b78a7a8 100644
--- a/exercises/basic-of-rust/src/conditions.rs
+++ b/exercises/basic-of-rust/src/conditions.rs
@@ -4,15 +4,25 @@
 // - another function call
 // - additional variables
 pub fn bigger(a: i32, b: i32) -> i32 {
-    todo!()
+    if a > b {
+        a
+    } else {
+        b
+    }
 }
 
 //Exercise 2
 // Input: Provide an arbitrary value of number
 // Check number is Positive or Negative or Zero
 // Output: &str
-fn check_number(number: u32) -> &'static str {
-    todo!()
+fn check_number(number: i32) -> &'static str {
+    if number < 0 {
+        return "Negative";
+    } else if number == 0 {
+        return "Zero";
+    } else {
+        return "Positive";
+    }
 }
 
 // Exercise 3
@@ -22,8 +32,10 @@ fn check_number(number: u32) -> &'static str {
 pub fn foo_if_fizz(fizzish: &str) -> &str {
     if fizzish == "fizz" {
         "foo"
+    } else if fizzish == "fuzz" {
+        "bar"
     } else {
-        1
+        "baz"
     }
 }
 
@@ -31,14 +43,25 @@ pub fn foo_if_fizz(fizzish: &str) -> &str {
 // Determine if a given year is a leap year
 // Implement logic
 fn is_leap_year(year: i32) -> bool {
-    todo!()
+    if year % 4 == 0 && year % 100 != 0 || year % 400 == 0 {
+        true
+    } else {
+        false
+    }
 }
 
 // Exercise 5
 // Calculate the factorial of a number
 // Implement logic
 fn factorial(n: u32) -> u32 {
-    todo!()
+    if n == 0 {
+        return 1;
+    }
+    let mut res: u32 = 1;
+    for i in 1..n + 1 {
+        res = res * i;
+    }
+    res
 }
 
 // Exercise 6
@@ -46,10 +69,17 @@ fn factorial(n: u32) -> u32 {
 // Implement logic
 
 fn is_prime(n: u32) -> bool {
-    todo!()
+    if n <= 1 {
+        return false;
+    }
+    for i in 2..n {
+        if n % i == 0 {
+            return false;
+        }
+    }
+    true
 }
 
-
 // Don't mind this for now :)
 #[cfg(test)]
 mod tests {
@@ -143,6 +173,4 @@ mod tests {
         assert_eq!(is_prime(10), false);
         assert_eq!(is_prime(15), false);
     }
-
-
-}
\ No newline at end of file
+}
diff --git a/exercises/basic-of-rust/src/functions.rs b/exercises/basic-of-rust/src/functions.rs
index c2b37e31..dbd51dbb 100644
--- a/exercises/basic-of-rust/src/functions.rs
+++ b/exercises/basic-of-rust/src/functions.rs
@@ -1,34 +1,52 @@
 // Exercise 1
-// Fix all errors 
-fn sum(x, y: i32) {
-    x + y;
+// Fix all errors
+fn sum(x: i32, y: i32) -> i32 {
+    x + y
 }
 
 //Exercise 2
 // Input: Provide an arbitrary value of n
 // Implement sum function: 1+2+3+..n
-// Output: Calculate sum 1 to n 
+// Output: Calculate sum 1 to n
 pub fn sum_one_to_n(n: u32) -> u32 {
     // your code for summing all digits from 1 to `n` (inclusive) should go
     // here (you can remove the sample return of `0`)
-    0
+    let mut res: u32 = 0;
+    for i in 1..n + 1 {
+        res = res + i;
+    }
+    return res;
 }
 
 // Exercise 3
 // Input: list of arbitrary numbers
 // Problem: Calculate the average of a list of numbers
-// Output: Average Number 
+// Output: Average Number
 fn calculate_average(numbers: &[f64]) -> f64 {
-    todo!()
+    if numbers.len() as u32 == 0 {
+        return 0.0;
+    }
+    let mut res: f64 = 0.0;
+    for num in numbers {
+        res = res + num;
+    }
+    res = res / numbers.len() as f64;
+
+    return res;
 }
 
 // Exercise 4
 // Calculate the sum of all even numbers in a list
 fn sum_even_numbers(numbers: &[i32]) -> i32 {
-    todo!()
+    let mut sum: i32 = 0;
+    for i in numbers {
+        if i % 2 == 0 {
+            sum = sum + i;
+        }
+    }
+    return sum;
 }
 
-
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -38,7 +56,7 @@ mod tests {
     fn sum_should_work() {
         let (x, y) = (1, 2);
         let s = sum(x, y);
-    
+
         assert_eq!(s, 3);
     }
 
@@ -73,7 +91,6 @@ mod tests {
         let numbers = [2.5, 4.8, 6.3, 1.7, 3.9];
         let result = calculate_average(&numbers);
         assert_eq!(result, 3.84);
-
     }
 
     // Test for exercise 3
@@ -83,7 +100,6 @@ mod tests {
         let numbers = [];
         let result = calculate_average(&numbers);
         assert_eq!(result, 0.0);
-
     }
 
     // Test for exercise 4
diff --git a/exercises/basic-of-rust/src/strings.rs b/exercises/basic-of-rust/src/strings.rs
index 998427d9..3aed43f7 100644
--- a/exercises/basic-of-rust/src/strings.rs
+++ b/exercises/basic-of-rust/src/strings.rs
@@ -1,24 +1,24 @@
 // Exercise 1
 #[allow(dead_code)]
 fn exercise1(color: &str) -> String {
-    todo!()
+    return color.to_string();
 }
 
 // Exercise 2
 // Fix all errors without adding newline
 fn exercise2() -> String {
-    let s = String::from("hello");
+    let mut s = String::from("hello");
     s.push(',');
-    s.push(" world");
-    s += "!".to_string();
+    s.push_str(" world");
+    s += "!" as &str;
     s
 }
 // Exercise 3
 // Fix errors without removing any line
 fn exercise3() -> String {
-    let s1 = String::from("hello,");
+    let s1 = String::from("hello, ");
     let s2 = String::from("world!");
-    let s3 = s1 + s2;
+    let s3 = s1 + s2.as_str();
     s3
 }
 
@@ -26,20 +26,32 @@ fn exercise3() -> String {
 // Reverse a string
 
 fn reverse_string(input: &str) -> String {
-    todo!()
+    let res = input as &str;
+    return res.chars().rev().collect();
 }
 
-
 // Exercise 5
 // Check if a string is a palindrome
 fn is_palindrome(word: &str) -> bool {
-    todo!()
+    if word.to_lowercase() == reverse_string(word).to_lowercase() {
+        return true;
+    }
+    false
 }
 
 // Exercise 6
 // Count the occurrences of a character in a string
 fn count_char_occurrences(string: &str, ch: char) -> usize {
-    todo!()
+    let mut cnt = 0;
+    let mut new_string = String::new();
+    new_string.push_str(string);
+
+    for k in new_string.chars() {
+        if k == ch {
+            cnt = cnt + 1;
+        }
+    }
+    return cnt;
 }
 
 #[cfg(test)]
@@ -63,7 +75,7 @@ mod tests {
     fn exercise3_work() {
         assert_eq!("hello, world!".to_string(), exercise3());
     }
-    
+
     // Test for exercise 4
     #[test]
     fn test_reverse_string() {
@@ -92,8 +104,7 @@ mod tests {
     #[test]
     fn test_count_char_occurrences() {
         assert_eq!(count_char_occurrences("Hello", 'l'), 2);
-        assert_eq!(count_char_occurrences("Rust is fun", 'u'), 1);
+        assert_eq!(count_char_occurrences("Rust is fun", 'u'), 2);
         assert_eq!(count_char_occurrences("Mississippi", 's'), 4);
     }
-
-}
\ No newline at end of file
+}
diff --git a/exercises/ownership-borrowing/src/lib.rs b/exercises/ownership-borrowing/src/lib.rs
index 46ccf53c..6645d855 100644
--- a/exercises/ownership-borrowing/src/lib.rs
+++ b/exercises/ownership-borrowing/src/lib.rs
@@ -3,8 +3,8 @@
 fn exercise1() {
     // Use as many approaches as you can to make it work
     let x = String::from("hello, world");
-    let y = x;
-    let z = x;
+    let y = &x;
+    let z = &x;
 }
 
 // Exercise 2
@@ -33,7 +33,7 @@ fn exercise3() {
 
     let values_number = values.len();
 
-    let additions: Vec<usize> = vec![0];
+    let additions: Vec<usize> = vec![0, 1];
 
     println!("{:?}", values_number);
 
@@ -41,7 +41,7 @@ fn exercise3() {
         let mut addition: f64 = 0.0;
 
         // Sumar valores en additions
-        for element_index in additions {
+        for &element_index in &additions {
             let addition_aux = values[element_index];
             addition = addition_aux + addition;
         }
@@ -50,9 +50,9 @@ fn exercise3() {
 
 // Exercise 4
 // Make it compile
-fn exercise4(value: u32) -> &'static str {
+fn exercise4(value: u32) -> String {
     let str_value = value.to_string(); // Convert u32 to String
-    let str_ref: &str = &str_value; // Obtain a reference to the String
+    let str_ref = str_value; // Obtain a reference to the String
     str_ref // Return the reference to the String
 }
 
@@ -65,11 +65,11 @@ fn exercise5() {
     let key = 3;
 
     let res = match my_map.get(&key) {
-        Some(child) => child,
+        Some(child) => child.to_string(),
         None => {
             let value = "3.0".to_string();
-            my_map.insert(key, value);
-            &value // HERE IT FAILS
+            my_map.insert(key, value.clone());
+            value // HERE IT FAILS
         }
     };
 
@@ -82,14 +82,14 @@ fn exercise5() {
 use std::io;
 
 fn exercise6() {
-    let mut prev_key: &str = "";
+    let mut prev_key = String::new();
 
     for line in io::stdin().lines() {
         let s = line.unwrap();
 
         let data: Vec<&str> = s.split("\t").collect();
         if prev_key.len() == 0 {
-            prev_key = data[0];
+            prev_key = data[0].to_string();
         }
     }
 }
@@ -97,11 +97,11 @@ fn exercise6() {
 // Exercise 7
 // Make it compile
 fn exercise7() {
-    let mut v: Vec<&str> = Vec::new();
+    let mut v: Vec<String> = Vec::new();
     {
         let chars = [b'x', b'y', b'z'];
         let s: &str = std::str::from_utf8(&chars).unwrap();
-        v.push(&s);
+        v.push(s.to_string());
     }
     println!("{:?}", v);
 }
@@ -109,8 +109,8 @@ fn exercise7() {
 // Exercise 8
 // Make it compile
 fn exercise8() {
-    let mut accounting = vec!["Alice", "Ben"];
-    
+    let mut accounting = vec!["Alice".to_string(), "Ben".to_string()];
+
     loop {
         let mut add_input = String::from("");
 
@@ -118,14 +118,17 @@ fn exercise8() {
             .read_line(&mut add_input)
             .expect("Failed to read line");
 
-        let add_vec: Vec<&str> = add_input.trim()[..].split_whitespace().collect();
+        let add_vec: Vec<String> = add_input.trim()[..]
+            .split_whitespace()
+            .map(|x| x.to_string())
+            .collect();
 
         if add_vec.len() < 1 {
             println!("Incorrect input, try again");
             continue;
         }
 
-        let person = add_vec[0];
+        let person = add_vec[0].to_string();
         accounting.push(person);
     }
 }