diff --git a/src/maths.rs b/src/maths.rs
index d53d778..c537270 100644
--- a/src/maths.rs
+++ b/src/maths.rs
@@ -32,6 +32,10 @@ impl Rational {
         Rational::new(self.denominator, self.numerator)
     }
 
+    pub fn left_shift(&self) -> Self {
+        Rational::new(self.numerator, self.denominator * 10)
+    }
+
     pub fn simplify(lhs: Rational, rhs: Rational) -> Self {
         let res = Rational::new(lhs.numerator * rhs.denominator, lhs.denominator * rhs.numerator);
         res.reduce()
diff --git a/src/parser/ast_builder.rs b/src/parser/ast_builder.rs
index cadc4cb..c462265 100644
--- a/src/parser/ast_builder.rs
+++ b/src/parser/ast_builder.rs
@@ -79,20 +79,22 @@ fn get_parentheses_map(tokens: &Vec<Token>) -> Vec<usize> {
 fn parse_number(string: &String, sign: i128) -> GaussianRational {
     let mut number = rational_zero();
     let mut is_floating = false;
-
+    let mut count = 0;
     for c in string.chars() {
         match c {
             '.' => is_floating = true,
             '0'..='9' => {
-                number = 10 * number + String::from(c).parse::<i128>().unwrap();
+                number = (10 * number) + String::from(c).parse::<i128>().unwrap();
                 if is_floating == true {
-                    number = number * Rational::new(1, 10);
+                    count += 1;
                 }
             }
             _ => unreachable!(),
         }
     }
-
+    for _ in 0..count {
+        number = number.left_shift();
+    }
     number = number * sign;
 
     GaussianRational::new(number, rational_zero())
@@ -117,23 +119,15 @@ fn check_parentheses(tokens: &Vec<Token>) -> bool {
 }
 
 pub fn build_ast(mut tokens: Vec<Token>) -> Node {
-    //let mut tokens_copy = tokens.clone();
-    //let mut not_done = true;
-
-    // Lowest prio : equal
     let split = tokens.iter().position(|x| x == &Token::Equal());
     if let Some(position) = split {
         return insert_operator_node(tokens, position);
     }
-
     while tokens.starts_with(&[Token::OpenParenthesis()]) && tokens.ends_with(&[Token::CloseParenthesis()]) && check_parentheses(&tokens) == true {
         tokens = tokens.split_off(1);
         tokens.pop();
     }
-
     let parentheses_map = get_parentheses_map(&tokens);
-    //let iter = zip(tokens, parentheses_map);
-    // Lowest prio : rightest minus or plus, also manages minus unary operator
     let split = tokens.iter().enumerate().rposition(|(i, x)| parentheses_map[i] == 0 && (x == &Token::Addition() || x == &Token::Substraction()));
     if let Some(position) = split {
         let tokens_right = tokens.split_off(position + 1);
@@ -152,13 +146,10 @@ pub fn build_ast(mut tokens: Vec<Token>) -> Node {
             rhs: Box::new(build_ast(tokens_right)),
         }
     }
-
-    // Lowest prio : righest times or divide or modulo
     let split = tokens.iter().enumerate().rposition(|(i, x)| parentheses_map[i] == 0 && (x == &Token::Multiplication() || x == &Token::Division() || x == &Token::Modulo()));
     if let Some(position) = split {
         return insert_operator_node(tokens, position);
     }
-    // Lowest prio : exponentiation
     let split = tokens.iter().enumerate().rposition(|(i, x)| parentheses_map[i] == 0 && x == &Token::Exponentiation());
     if let Some(position) = split {
         return insert_operator_node(tokens, position);